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Número de publicaciónUS4540753 A
Tipo de publicaciónConcesión
Número de solicitudUS 06/504,582
Fecha de publicación10 Sep 1985
Fecha de presentación15 Jun 1983
Fecha de prioridad15 Jun 1983
TarifaPagadas
También publicado comoCA1228699A, CA1228699A1, DE3483497D1, EP0129414A2, EP0129414A3, EP0129414B1, US4874820
Número de publicación06504582, 504582, US 4540753 A, US 4540753A, US-A-4540753, US4540753 A, US4540753A
InventoresCharles Cozewith, Shiaw Ju, Gary W. VerStrate
Cesionario originalExxon Research & Engineering Co.
Exportar citaBiBTeX, EndNote, RefMan
Enlaces externos: USPTO, Cesión de USPTO, Espacenet
Narrow MWD alpha-olefin copolymers
US 4540753 A
Resumen
The present invention relates to novel copolymers of alpha-olefins comprised of intramolecularly heterogeneous and intermolecularly homogeneous copolymer chains.
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Reclamaciones(24)
What is claimed is:
1. In a polymerization process for producing copolymer in the form of copolymer chains, from a reaction mixture comprised of catalyst, ethylene, and at least one other alpha-olefin monomer, the improvement which comprises conducting the polymerization:
(a) in at least one mix-free reactor,
(b) with essentially one active catalyst species,
(c) using at least one reaction mixture which is essentially transfer agent-free, and
(d) in such a manner and under conditions sufficient to initiate propagation of essentially all of said copolymer chains simultaneously, wherein the copolymer chains are dispersed within the reaction mixture.
2. A process according to claim 1, wherein the catalyst comprises hydrocarbon-soluble vanadium compound and organo-aluminum compound which react to form essentially one active catalyst species, at least one of the vanadium compound and organo-aluminum compound containing a valence-bonded halogen.
3. A process according to claim 1 or 2, wherein the inlet temperature of the reaction mixture is about -50° C. to 150° C.
4. A process according to claim 3, wherein the maximum outlet temperature of the reaction mixture is about 200° C.
5. A process according to claim 3, wherein the catalyst components are premixed, and wherein the polymerization is a solution polymerization.
6. A process according to claim 5, wherein the catalyst components are aged for at least about 0.5 seconds.
7. A process according to claim 2, wherein the mole ratio of aluminum to vanadium in the catalyst is about 2 to 25.
8. A process according to claim 5, wherein the reaction mixture leaving the reactor has a copolymer concentration of about 3 to 15% on a weight of copolymer per weight of solvent basis.
9. A process according to claim 1, wherein the catalyst comprises a Ziegler catalyst.
10. a process according to claim 3, wherein the maximum outlet temperature of the reaction mixture is about 50° C.
11. A process according to claim 8, wherein the catalyst comprises components that are premixed and then aged for about 1 to 50 seconds.
12. A process according to claim 8, wherein the mole ratio of aluminum to vanadium in the catalyst is about 4 to 15.
13. A process according to claim 12, wherein the polymerization is conducted in a solvent for the reaction mixture, and wherein the reaction mixture leaving the reactor has a copolymer concentration of about 3% to 10% on a weight of polymer per weight of solvent basis.
14. A process according to claim 2, wherein the catalyst comprises:
(a) hydrocarbon-soluble vanadium compound selected from the group consisting of: ##STR3## where x=0-3 and R=hydrocarbon radical; VCl4 ;
VO(AcAc)2,
where AcAc=acetyl acetonate
V(AcAc)3,
where AcAc=acetyl acetonate
VOClx (AcAc)3-x,
where x=1 or 2 and AcAc=acetyl acetonate; and
VCl3.nB,
where n=2-3 and B=Lewis base capable of forming hydrocarbon-soluble complexes with VCl3 ; and
(b) organo-aluminum compound selected from the group consisting of:
AlR3
AlR2 Cl,
Al2 R3 Cl3,
AlRCl2,
AlR'RCl,
Al(OR')R2,
R2 Al-OAlR2, and
AlR2 I,
where R and R' are hydrocarbon radicals.
15. A process according to claim 2, wherein the catalyst comprises VCl4 and Al2 R3 Cl3.
16. A process according to claim 4, wherein the maximum outlet temperature of the reaction mixture is about 70° C.
17. A process according to claim 16, wherein the polymerization is adiabatic.
18. A process according to claim 17, wherein the catalyst comprises one active species which provides for at least 65% of the total copolymer produced.
19. A process according to claim 18, which is continuous and is conducted in hexane solvent.
20. A process according to claim 1, wherein said copolymer product is cured.
21. A process according to claim 1, wherein said polymerization is conducted in at least one tubular reactor.
22. A process according to claim 21, wherein said reaction mixture further comprises diene, and wherein at least one of said ethylene, other alpha-olefin monomer and diene are fed to said tubular reactor at multiple feed sites.
23. A process according to claim 1 or 14, wherein the copolymer produced has a total ethylene content of greater than about 25% on a weight basis.
24. A process according to claim 1 or 14, wherein the catalyst components are premixed.
Descripción
BACKGROUND OF THE INVENTION

The present invention relates to novel copolymers of alpha-olefins. More specifically, it relates to novel copolymers of ethylene with other alpha-olefins comprised of copolymer chains with compositions which are intramolecularly heterogeneous and intermolecularly homogeneous, as well as, to a process for making these copolymers and their use in lube oil and elastomer applications.

For convenience, certain terms that are repeated throughout the present specification are defined below:

a. Inter-CD defines the compositional variation, in terms of ethylene content, among polymer chains. It is expressed as the minimum deviation (analogous to a standard deviation) in terms of weight percent ethylene from the average ethylene composition for a given copolymer sample needed to include a given weight percent of the total copolymer sample which is obtained by excluding equal weight fractions from both ends of the distribution. The deviation need not be symmetrical. When expressed as a single number for example 15% Inter-CD, it shall mean the larger of the positive or negative deviations. For example, for a Gaussian compositional distribution, 95.5% of the polymer is within 20 wt.% ethylene of the mean if the standard deviation is 10%. The Inter-CD for 95.5 wt.% of the polymer is 20 wt.% ethylene for such a sample.

b. Intra-CD is the compositional variation, in terms of ethylene, within a copolymer chain. It is expressed as the minimum difference in weight (wt.) % ethylene that exists between two portions of a single copolymer chain, each portion comprising at least 5 weight % of the chain.

c. Molecular weight distribution (MWD) is a measure of the range of molecular weights within a given copolymer sample. It is characterized in terms of at least one of the ratios of weight average to number average molecular weight, Mw /Mn, and Z average to weight average molecular weight, Mz /Mw, where: ##EQU1## Ni is the number of molecules of weight Mi. d. Viscosity Index (V.I.) is the ability of a lubricating oil to accommodate increases in temperature with a minimum decrease in viscosity. The greater this ability, the higher the V.I.

Ethylene-propylene copolymers, particularly elastomers, are important commercial products. Two basic types of ethylene-propylene copolymers are commercially available. Ethylene-propylene copolymers (EPM) are saturated compounds requiring vulcanization with free radical generators such as organic peroxides. Ethylene-propylene terpolymers (EPDM) contain a small amount of non-conjugated diolefin, such as dicyclopentadiene; 1,4-hexadiene or ethylidene norbornene, which provides sufficient unsaturation to permit vulcanization with sulfur. Such polymers that include at least two monomers, i.e., EPM and EPDM, will hereinafter be collectively referred to as copolymers.

These copolymers have outstanding resistance to weathering, good heat aging properties and the ability to be compounded with large quantities of fillers and plasticizers resulting in low cost compounds which are particularly useful in automotive and industrial mechanical goods applications. Typical automotive uses are tire sidewalls, inner tubes, radiator and heater hose, vacuum tubing, weather stripping and sponge doorseals and Viscosity Index (V.I.) improvers for lubricating oil compositions. Typical mechanical goods uses are for appliance, industrial and garden hoses, both molded and extruded sponge parts, gaskets and seals and conveyor belt covers. These copolymers also find use in adhesives, appliance parts as in hoses and gaskets, wire and cable and plastics blending.

As can be seen from the above, based on their respective properties, EPM and EPDM find many, varied uses. It is known that the properties of such copolymers which make them useful in a particular application are, in turn, determined by their composition and structure. For example, the ultimate properties of an EPM or EPDM copolymer are determined by such factors as composition, compositional distribution, sequence distribution, molecular weight, and molecular weight distribution (MWD).

The efficiency of peroxide curing depends on composition. As the ethylene level increases, it can be shown that the "chemical" crosslinks per peroxide molecule increases. Ethylene content also influences the rheological and processing properties, because crystallinity, which acts as physical crosslinks, can be introduced. The crystallinity present at very high ethylene contents may hinder processibility and may make the cured product too "hard" at temperatures below the crystalline melting point to be useful as a rubber.

Milling behavior of EPM or EPDM copolymers varies radically with MWD. Narrow MWD copolymers crumble on a mill, whereas broad MWD materials will band under conditions encountered in normal processing operations. At the shear rates encountered in processing equipment, broader MWD copolymer has a substantially lower viscosity than narrower MWD polymer of the same weight average molecular weight or low strain rate viscosity.

Thus, there exists a continuing need for discovering polymers with unique properties and compositions. This is easily exemplified with reference to the area of V.I. improvers for lubricating oils.

A motor oil should not be too viscous at low temperatures so as to avoid serious frictional losses, facilitate cold starting and provide free oil circulation right from engine startup. On the other hand, it should not be too thin at working temperatures so as to avoid excessive engine wear and excessive oil consumption. It is most desirable to employ a lubricating oil which experiences the least viscosity change with changes in temperature.

The ability of a lubricating oil to accommodate increases in temperature with a minimum decrease in viscosity is indicated by its Viscosity Index (V.I.). The greater this ability, the higher the V.I.

Polymeric additives have been extensively used in lubricating oil compositions to impart desirable viscosity-temperature characteristics to the compositions. For example, lubricating oil compositions which use EPM or EPDM copolymers or, more generally, ethylene-(C3 -C18) alpha-olefin copolymers, as V.I. improvers are well known. These additives are designed to modify the lubricating oil so that changes in viscosity occurring with variations in temperature are kept as small as possible. Lubricating oils containing such polymeric additives essentially maintain their viscosity at higher temperatures while at the same time maintaining desirable low viscosity fluidity at engine starting temperatures.

Two important properties (although not the only required properties as is known) of these additives relate to low temperature performance and shear stability. Low temperature performance relates to maintaining low viscosity at very low temperatures, while shear stability relates to the resistance of the polymeric additives to being broken down into smaller chains.

The present invention is drawn to a novel copolymer of ethylene and at least one other alpha-olefin monomer which copolymer is intramolecularly heterogeneous and intermolecularly homogeneous. Furthermore, the MWD of the copolymer is very narrow. It is well known that the breadth of the MWD can be characterized by the ratios of various molecular weight averages. For example, an indication of a narrow MWD in accordance with the present invention is that the ratio of weight to number average molecular weight (Mw /Mn) is less than 2. Alternatively, a ratio of the Z-average molecular weight to the weight average molecular weight (Mz /Mw) of less than 1.8 typifies a narrow MWD in accordance with the present invention. It is known that the property advantages of copolymers in accordance with the present invention are related to these ratios. Small weight fractions of material can disproportionately influence these ratios while not significantly altering the property advantages which depend on them. For instance, the presence of a small weight fraction (e.g. 2%) of low molecular weight copolymer can depress Mn, and thereby raise Mw /Mn above 2 while maintaining Mz /Mw less than 1.8. Therefore, polymers, in accordance with the present invention, are characterized by having at least one of Mw /Mn less than 2 and Mz /Mw less than 1.8. The copolymer comprises chains within which the ratio of the monomers varies along the chain length. To obtain the intramolecular compositional heterogeneity and narrow MWD, the copolymers in accordance with the present invention are preferably made in a tubular reactor. It has been discovered that to produce such copolymers requires the use of numerous heretofore undisclosed method steps conducted within heretofore undisclosed preferred ranges. Accordingly, the present invention is also drawn to a method for making the novel copolymers of the present invention.

Copolymers in accordance with the present invention have been found to have improved properties in lubricating oil. Accordingly, the present invention is also drawn to a novel oil additive composition which comprises basestock mineral oil of lubricating viscosity containing an effective amount of a viscosity index improver being copolymer in accordance with the present invention.

DESCRIPTION OF THE PRIOR ART

Representative prior art dealing with tubular reactors to make copolymers are as follows:

In "Polymerization of ethylene and propylene to amorphous copolymers with catalysts of vanadium oxychloride and alkyl aluminum halides"; E. Junghanns, A. Gumboldt and G. Bier; Makromol. Chem., v. 58 (12/12/62): 18-42, the use of a tubular reactor to produce ethylene-propylene copolymer is disclosed in which the composition varies along the chain length. More specifically, this reference discloses the production in a tubular reactor of amorphous ethylene-propylene copolymers using Ziegler catalysts prepared from vanadium compound and aluminum alkyl. It is disclosed that at the beginning of the tube ethylene is preferentially polymerized, and if no additional make-up of the monomer mixture is made during the polymerization the concentration of monomers changes in favor of propylene along the tube. If is further disclosed that since these changes in concentrations take place during chain propagation, copolymer chains are produced which contain more ethylene on one end than at the other end. It is also disclosed that copolymers made in a tube are chemically non-uniform, but fairly uniform as regards molecular weight distribution. Using the data reported in their FIG. 17 for copolymer prepared in the tube, it was estimated that the M.sub. w /Mn ratio for this copolymer was 1.6, and from their FIG. 18 that the intermolecular compositional dispersity (Inter-CD, explained in detail below) of this copolymer was greater than 15%.

"Laminar Flow Polymerization of EPDM Polymer"; J. F. Wehner; ACS Symposium Series 65 (1978); pp 140-152 discloses the results of computer simulation work undertaken to determine the effect of tubular reactor solution polymerization with Ziegler catalysts on the molecular weight distribution of the polymer product. The specific polymer simulated was an elastomeric terpolymer of ethylene-propylene-1,4-hexadiene. On page 149, it is stated that since the monomers have different reactivities, a polymer of varying composition is obtained as the monomers are depleted. However, whether the composition varies inter-or intramolecularly is not distinguished. In Table III on page 148, various polymers having Mw /Mn of about 1.3 are predicted. In the third paragraph on page 144, it is stated that as the tube diameter increases, the polymer molecular weight is too low to be of practical interest, and it is predicted that the reactor will plug. It is implied in the first paragraph on page 149 that the compositional dispersity produced in a tube would be detrimental to product quality.

U.S. Pat. No. 3,681,306 to Wehner is drawn to a process for producing ethylene/higher alpha-olefin copolymers having good processability, by polymerization in at least two consecutive reactor stages. According to this reference, this two-stage process provides a simple polymerization process that permits tailor-making ethylene/alpha-olefin copolymers having predetermined properties, particularly those contributing to processability in commercial applications such as cold-flow, high green strength and millability. According to this reference, the inventive process is particularly adapted for producing elastomeric copolymers, such as ethylene/propylene/5-ethylidene-2-norbornene, using any of the coordination catalysts useful for making EPDM. The preferred process uses one tubular reactor followed by one pot reactor. However, it is also disclosed that one tubular reactor could be used, but operated at different reaction conditions to simulate two stages. As is seen from column 2, lines 14-20, the inventive process makes polymers of broader MWD than those made in a single stage reactor. Although intermediate polymer from the first (pipeline) reactor is disclosed as having a ratio of Mw /Mn of about 2, as disclosed in column 5, lines 54-57, the final polymers produced by the inventive process have an Mw /Mn of 2.4 to 5.

U.S. Pat. No. 3,625,658 to Closon discloses a closed circuit tubular reactor apparatus with high recirculation rates of the reactants which can be used to make elastomers of ethylene and propylene. With particular reference to FIG. 1, a hinged support 10 for vertical leg 1 of the reactor allows for horizontal expansion of the bottom leg thereof and prevents harmful deformations due to thermal expansions, particularly those experienced during reactor clean out.

U.S. Pat. No. 4,065,520 to Bailey et al discloses the use of a batch reactor to make ethylene copolymers, including elastomers, having broad compositional distributions. Several feed tanks for the reactor are arranged in series, with the feed to each being varied to make the polymer. The products made have crystalline to semi-crystalline to amorphous regions and gradient changes in between. The catalyst system can use vanadium compounds alone or in combination with titanium compound and is exemplified by vanadium oxy-trichloride and diisobutyl aluminum chloride. In all examples titanium compounds are used. In several examples hydrogen and diethyl zinc, known transfer agents, are used. The polymer chains produced have a compositionally disperse first length and uniform second length. Subsequent lengths have various other compositional distributions.

In "Estimation of Long-Chain Branching in Ethylene-Propylene Terpolymers from Infinite-Dilution Viscoelastic Properties"; Y. Mitsuda, J. Schrag, and J. Ferry; J. Appl. Pol. Sci., 18, 193 (1974) narrow MWD copolymers of ethylene-propylene are disclosed. For example, in TABLE II on page 198, EPDM copolymers are disclosed which have Mw /Mn of from 1.19 to 1.32.

In "The Effect of Molecular Weight and Molecular Weight Distribution on the Non-Newtonian Behavior of Ethylene-Propylene-Diene Polymers; Trans. Soc. Rheol., 14, 83 (1970); C. K. Shih, a whole series of compositionally homogeneous fractions were prepared and disclosed. For example, the data in TABLE I discloses polymer Sample B having a high degree of homogeneity. Also, based on the reported data, the MWD of the sample is very narrow. However, the polymers are not disclosed as having intramolecular dispersity.

Representative prior art dealing with ethylene-alpha-olefin copolymers as lubricating oil additives are as follows:

U.S. Pat. No. 3,697,429 to Engel et al discloses a blend of ethylene-propylene copolymers having different ethylene contents, i.e., a first copolymer of 40-83 wt.% ethylene and Mw /Mn less than about 4.0 (preferably less than 2.6, e.g. 2.2) and a second copolymer of 3-70 wt.% ethylene and Mw /Mn less than 4.0, with the content of the first differing from the second by at least 4 wt.% ethylene. These blends, when used as V.I. improvers in lubricating oils, provide suitable low temperature viscosity properties with minimal adverse interaction between the oil pour depressant and the ethylene-propylene copolymer.

U.S. Pat. No. 3,522,180 discloses copolymers of ethylene and propylene having a number average molecular weight of 10,000 to 40,000 and a propylene content of 20 to 70 mole percent as V.I. improvers in lube oils. The preferred Mw /Mn of these copolymers is less than about 4.0.

U.S. Pat. No. 3,691,078 to Johnston et al discloses the use of ethylene-propylene copolymers containing 25-55 wt.% ethylene which have a pendent index of 18-33 and an average pendent size not exceeding 10 carbon atoms as lube oil additives. The Mw /Mn is less than about 8. These additives impart to the oil good low temperature properties with respect to viscosity without adversely affecting pour point depressants.

U.S. Pat. No. 3,551,336 to Jacobson et al discloses the use of ethylene copolymers of 60-80 mole % ethylene, having no more than 1.3 wt.% of a polymer fraction which is insoluble in normal decane at 55° C. as an oil additive. Minimization of this decane-insoluble fraction in the polymer reduces the tendency of the polymer to form haze in the oil, which haze is evidence of low temperature instability probably caused by adverse interaction with pour depressant additives. The Mw /Mn of these copolymers is "surprisingly narrow" and is less than about 4.0, preferably less than 2.6, e.g., 2.2.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings depict, for illustration purposes only, processes embodied by the present invention, wherein:

FIG. 1 is a schematic representation of a process for producing polymer in accordance with the present invention,

FIG. 2 schematically illustrates how the process depicted in FIG. 1 can be integrated into a lube oil additive process,

FIG. 3 is a graphical illustration of a technique for determining Intra-CD of a copolymer,

FIG. 4 graphically illustrates various copolymer structures that can be attained using processes in accordance with the present invention,

FIG. 5 is a graphic representation of polymer concentration vs. residence time for consideration with Example 2 herein, and

FIG. 6 is a graphic representation of intramolecular compositional dispersity (Intra-CD) of copolymer chains made with additional monomer feeds downstream of the reactor inlet as in Example 3.

DETAILED DESCRIPTION OF THE INVENTION

As already noted above, the present invention is drawn to novel copolymer of ethylene and at least one other alpha-olefin monomer which copolymer is intramolecularly heterogeneous and intermolecularly homogeneous and has an MWD characterized by at least one of Mw /Mn of less than 2 and Mz /Mw of less than 1.8. More specifically, copolymer in accordance with the present invention comprises intramolecularly heterogeneous chains wherein at least two portions of an individual intramolecularly heterogeneous chain, each portion comprising at least 5 weight percent of the chain, differ in composition from one another by at least 5 weight percent ethylene, wherein the intermolecular compositional dispersity of the polymer is such that 95 wt.% of the polymer chains have a composition 15% or less different in ethylene from the average weight percent ethylene composition, and wherein the copolymer is characterized by at least one of a ratio of Mw /Mn of less than 2 and a ratio of Mz /Mw of less than 1.8.

Since the present invention is considered to be most preferred in the context of ethylene-propylene (EPM) or ethylene-propylene-diene (EPDM) copolymers, it will be described in detail in the context of EPM and/or EPDM.

Copolymer in accordance with the present invention is preferably made in a tubular reactor. When produced in a tubular reactor with monomer feed only at the tube inlet, it is known that at the beginning of the tubular reactor ethylene, due to its high reactivity, will be preferentially polymerized. However, the concentration of monomers changes along the tube in favor of propylene as the ethylene is depleted. The result is copolymer chains which are higher in ethylene concentration in the chain segments grown near the reactor inlet (as defined at the point at which the polymerization reaction commences), and higher in propylene concentration in the chain segments formed near the reactor outlet. An illustrative copolymer chain of ethylene-propylene is schematically presented below with E representing ethylene constituents and P representing propylene constituents in the chain: ##STR1##

As can be seen from this illustrative schematic chain, the far left-hand segment (1) thereof represents that portion of the chain formed at the reactor inlet where the reaction mixture is proportionately richer in the more reactive constituent ethylene. This segment comprises four ethylene molecules and one propylene molecule. However, as subsequent segments are formed from left to right with the more reactive ethylene being depleted and the reaction mixture proportionately increasing in propylene concentration, the subsequent chain segments become more concentrated in propylene. The resulting chain is intramolecularly heterogeneous.

In the event that more than two monomers are used, e.g., in the production of EPDM using a diene termonomer, for purposes of describing the present invention all properties related to homogeneity and heterogeneity will refer to the relative ratio of ethylene to the other monomers in the chain. The property, of the copolymer discussed herein, related to intramolecular compositional dispersity (compositional variation within a chain) shall be referred to as Intra-CD, and that related to intermolecular compositional dispersity (compositional variation between chains) shall be referred to as Inter-CD.

For copolymers in accordance with the present invention, composition can vary between chains as well as along the length of the chain. An object of this invention is to minimize the amount of interchain variation. The Inter-CD can be characterized by the difference in composition between some fraction of the copolymer and the average composition, as well as by the total difference in composition between the copolymer fractions containing the highest and lowest quantity of ethylene. Techniques for measuring the breadth of the Inter-CD are known as illustrated by Junghanns et al wherein a p-xylene-dimethylformamide solvent/non-solvent was used to fractionate copolymer into fractions of differing intermolecular composition. Other solvent/non-solvent systems can be used such as hexane-2-propanol, as will be discussed in more detail below.

The Inter-CD of copolymer in accordance with the present invention is such that 95 wt.% of the copolymer chains have an ethylene composition that differs from the average weight percent ethylene composition by 15 wt.% or less. The preferred Inter-CD is about 13% or less, with the most preferred being about 10% or less. In comparison, Junghanns et al found that their tubular reactor copolymer had an Inter-CD of greater than 15 weight %.

Broadly, the Intra-CD of copolymer in accordance with the present invention is such that at least two portions of an individual intramolecularly heterogeneous chain, each portion comprising at least 5 weight percent of the chain, differ in composition from one another by at least 5 weight percent ethylene. Unless otherwise indicated, this property of Intra-CD as referred to herein is based upon at least two 5 weight percent portions of copolymer chain. The Intra-CD of copolymer in accordance with the present invention can be such that at least two portions of copolymer chain differ by at least 10 weight percent ethylene. Differences of at least 20 weight percent, as well as, of at least 40 weight percent ethylene are also considered to be in accordance with the present invention.

The experimental procedure for determining Intra-CD is as follows. First the Inter-CD is established as described below, then the polymer chain is broken into fragments along its contour and the Inter-CD of the fragments is determined. The difference in the two results is due to Intra-CD as can be seen in the illustrative example below.

Consider a heterogeneous sample polymer containing 30 monomer units. It consists of 3 molecules designated A, B, C.

A EEEEPEEEPEEEPPEEPPEPPPEPPPPPPP

B EEEEEPEEEPEEEPPEEEPPPEPPPEEPPP

C EEPEEEPEEEPEEEPEEEPPEEPPPEEPPP

Molecule A is 36.8 wt. % ethylene, B is 46.6%, and C is 50% ethylene. The average ethylene content for the mixture is 44.3%. For this sample the Inter-CD is such that the highest ethylene polymer contains 5.7% more ethylene than the average while the lowest ethylene content polymer contains 7.5% less ethylene than the average. Or, in other words, 100 weight % of the polymer is within +5.7% and -7.5% ethylene about an average of 44.3%. Accordingly, the Inter-CD is 7.5% when the given weight % of the polymer is 100%. The distribution may be represented graphically as by curve 1 in FIG. 3.

If the chains are broken into fragments, there will be a new Inter-CD. For simplicity, consider first breaking only molecule A into fragments shown by the slashes as follows:

EEEEP/EEEPE/EEPPE/EPPEP/PPEPP/PPPPP

Portions of 72.7%, 72.7%, 50%, 30.8%, 14.3% and 0% ethylene are obtained. If molecules B and C are similarly broken and the weight fractions of similar composition are grouped the new Inter-CD shown by curve 2 in FIG. 3 is obtained. The difference between the two curves in the figure is due to Intra-CD.

Consideration of such data, especially near the end point ranges, demonstrates that for this sample at least 5% of the chain contour represented by the cumulative weight % range (a) differs in composition from another section by at least 15% ethylene shown as (b), the difference between the two curves. The difference in composition represented by (b) cannot be intermolecular. If it were, the separation process for the original polymer would have revealed the higher ethylene contents seen only for the degraded chain.

The compositional differences shown by (b) and (d) in the figure between original and fragmented chains give minimum values for Intra-CD. The Intra-CD must be at least that great, for chain sections have been isolated which are the given difference in composition (b) or (d) from the highest or lowest composition polymer isolated from the original. We know in this example that the original polymer represented at (b) had sections of 72.7% ethylene and 0% ethylene in the same chain. It is highly likely that due to the inefficiency of the fractionation process any real polymer with Intra-CD examined will have sections of lower or higher ethylene connected along its contour than that shown by the end points of the fractionation of the original polymer. Thus, this procedure determines a lower bound for Intra-CD. To enhance the detection, the original whole polymer can be fractionated (e.g., separate molecule A from molecule B from molecule C in the hypothetical example) with these fractions refractionated until they show no (or less) Inter-CD. Subsequent fragmentation of this intermolecularly homogeneous fraction now reveals the total Intra-CD. In principle, for the example, if molecule A were isolated, fragmented, fractionated and analyzed, the Intra-CD for the chain sections would be 72.7-0%32 72.7% rather than 72.7-50%=22.7% seen by fractionating the whole mixture of molecules A, B, and C.

In order to determine the fraction of a polymer which is intramolecularly heterogeneous in a mixture of polymers combined from several sources the mixture must be separated into fractions which show no further heterogeneity upon subsequent fractionation. These fractions are subsequently fractured and fractionated to reveal which are heterogeneous.

The fragments into which the original polymer is broken should be large enough to avoid end effects and to give a reasonable opportunity for the normal statistical distribution of segments to form over a given monomer conversion range in the polymerization. Intervals of ca 5 weight % of the polymer are convenient. For example, at an average polymer molecular weight of about 105, fragments of ca 5000 molecular weight are appropriate. A detailed mathematical analysis of plug flow or batch polymerization indicates that the rate of change of composition along the polymer chain contour will be most severe at high ethylene conversion near the end of the polymerization. The shortest fragments are needed here to show the low ethylene content sections.

The best available technique for determination of compositional dispersity for non-polar polymers is solvent/non-solvent fractionation which is based on the thermodynamics of phase separation. This technique is described in "Polymer Fractionation", M. Cantow editor, Academic 1967, p. 341 ff and in H. Inagaki, T. Tanaku, Developments in Polymer Characterization, 3, 1 (1982). These are incorporated herein by reference.

For non-crystalline copolymers of ethylene and propylene, molecular weight governs insolubility more than does composition in a solvent/non-solvent solution. High molecular weight polymer is less soluble in a given solvent mix. Also, there is a systematic correlation of molecular weight with ethylene content for the polymers described herein. Since ethylene polymerizes much more rapidly than propylene, high ethylene polymer also tends to be high in molecular weight. Additionally, chains rich in ethylene tend to be less soluble in hydrocarbon/polar non-solvent mixtures than propylene-rich chains. Thus the high molecular weight, high ethylene chains are easily separated on the basis of thermodynamics.

A fractionation procedure is as follows: Unfragmented polymer is dissolved in n-hexane at 23° C. to form ca a 1% solution (1 g polymer/100 cc hexane). Isopropyl alcohol is titrated into the solution until turbidity appears at which time the precipitate is allowed to settle. The supernatant liquid is removed and the precipitate is dried by pressing between Mylar® (polyethylene terphthalate) film at 150° C. Ethylene content is determined by ASTM method D-3900. Titration is resumed and subsequent fractions are recovered and analyzed until 100% of the polymer is collected. The titrations are ideally controlled to produce fractions of 5-10% by weight of the original polymer especially at the extremes of composition.

To demonstrate the breadth of the distribution, the data are plotted as % ethylene versus the cumulative weight of polymer as defined by the sum of half the weight % of the fraction of that composition plus the total weight % of the previously collected fractions.

Another portion of the original polymer is broken into fragments. A suitable method for doing this is by thermal degradation according to the following procedure: In a sealed container in a nitrogen-purged oven, a 2 mm thick layer of the polymer is heated for 60 minutes at 330° C. This should be adequate to reduce a 105 molecular weight polymer to fragments of ca 5000 molecular weight. Such degradation does not change the average ethylene content of the polymer.

This polymer is fractionated by the same procedure as the high molecular weight precursor. Ethylene content is measured, as well as molecular weight on selected fractions.

Ethylene content is measured by ASTM-D3900 for ethylene-propylene copolymers between 35 and 85 wt.% ethylene. Above 85% ASTM-D2238 can be used to obtain methyl group concentrations which are related to percent ethylene in an unambiguous manner for ethylene-propylene copolymers. When comonomers other than propylene are employed no ASTM tests covering a wide range of ethylene contents are available, however, proton and carbon 13 nuclear magnetic resonance can be employed to determine the composition of such polymers. These are absolute techniques requiring no calibration when operated such that all nucleii contribute equally to the spectra. For ranges not covered by the ASTM tests for ethylene-propylene copolymers, these nuclear magnetic resonance methods can also be used.

Molecular weight and molecular weight distribution are measured using a Waters 150 gel permeation chromatograph equipped with a Chromatix KMX-6 on-line light scattering photometer. The system is ued at 135° C. with 1,2,4 trichlorobenzene as mobile phase. Showdex (Showa-Denko America, Inc.) polystyrene gel columns 802, 803, 804 and 805 are used. This technique is discussed in "Liquid Chromatography of Polymers and Related Materials III', J. Cazes editor. Marcel Dekker, 1981, p. 207 (incorporated herein by reference). No corrections for column spreading are employed; however, data on generally accepted standards, e.g., National Bureau of Standards Polyethene 1484 and anionically produced hydrogenated polyisoprenes (an alternating ethylenepropylene copolymer) demonstrate that such corrections on Mw /Mn or Mz /Mw are less than 0.05 unit. Mw /Mn is calculated from an elution time-molecular weight relationship whereas Mz /Mw is evaluated using the light scattering photometer. The numerical analyses can be performed using the commercially available computer software GPC2, MOLWT2 available from LDC/Milton Roy-Riviera Beach, Fla.

As already noted, copolymers in accordance with the present invention are comprised of ethylene and at least one other alpha-olefin. It is believed that such alpha-olefins could include those containing 3 to 18 carbon atoms, e.g., propylene, butene-1, pentene-1, etc. Alpha-olefins of 3 to 6 carbons are preferred due to economic considerations. The most preferred copolymers in accordance with the present invention are those comprised of ethylene and propylene or ethylene, propylene and diene.

As is well known to those skilled in the art, copolymers of ethylene and higher alpha-olefins such as propylene often include other polymerizable monomers. Typical of these other monomers may be non-conjugated dienes such as the following non-limiting examples:

a. straight chain acyclic dienes such as: 1,4-hexadiene; 1,6-octadiene;

b. branched chain acyclic dienes such as: 5-methyl-1, 4-hexadiene; 3,7-dimethyl-1,6-octadiene; 3,7-dimethyl-1,7-octadiene and the mixed isomers of dihydro-myrcene and dihydroocinene;

c. single ring alicyclic dienes such as: 1,4-cyclohexadiene; 1,5-cyclooctadiene; and 1,5-cyclododecadiene;

d. multi-ring alicyclic fused and bridged ring dienes such as: tetrahydroindene; methyltetrahydroindene; dicyclopentadiene; bicyclo-(2,2,1)-hepta-2,5-diene; alkenyl, alkylidene, cycloalkenyl and cycloalkylidene norbornenes such as 5-methylene-2-norbornene (MNB), 5-ethylidene-2-norbornene (ENB), 5-propyl-2-norbornene, 5-isopropylidene-2-norbornene, 5-(4-cyclopentenyl)-2-norbornene; 5-cyclohexylidene-2-norbornene.

Of the non-conjugated dienes typically used to prepare these copolymers, dienes containing at least one of the double bonds in a strained ring are preferred. The most preferred diene is 5-ethylidene-2-norbornene (ENB). The amount of diene (wt. basis) in the copolymer could be from about 0% to 20% with 0% to 15% being preferred. The most preferred range is 0% to 10%.

As already noted, the most preferred copolymer in accordance with the present invention is ethylene-propylene or ethylene-propylene-diene. In either event, the average ethylene content of the copolymer could be as low as about 10% on a weight basis. The preferred minimum is about 25%. A more preferred minimum is about 30%. The maximum ethylene content could be about 90% on a weight basis. The preferred maximum is about 85%, with the most preferred being about 80%.

The molecular weight of copolymer made in accordance with the present invention can vary over a wide range. It is believed that the weight average molecular weight could be as low as about 2,000. The preferred minimum is about 10,000. The most preferred minimum is about 20,000. It is believed that the maximum weight average molecular weight could be as high as about 12,000,000. The preferred maximum is about 1,000,000. The most preferred maximum is about 750,000.

Another feature of copolymer made in accordance with the present invention is that the molecular weight distribution (MWD) is vary narrow, as characterized by at least one of a ratio of Mw /Mn of less than 2 and a ratio of Mz /Mw of less than 1.8. As relates to EPM and EPDM, some typical advantages of such copolymers having narrow MWD are greater resistance to shear degradation, and when compounded and vulcanized, faster cure and better physical properties than broader MWD materials. Particularly for oil additive applications, the preferred copolymers have Mw /Mn less than about 1.6, with less than about 1.4 being most preferred. The preferred Mz /Mw is less than about 1.5, with less than about 1.3 being most preferred.

Processes in accordance with the present invention produce copolymer by polymerization of a reaction mixture comprised of catalyst, ethylene and at least one additional alpha-olefin monomer. Solution polymerizations are preferred.

Any known solvent for the reaction mixture that is effective for the purpose can be used in conducting solution polymerizations in accordance with the present invention. For example, suitable solvents would be hydrocarbon solvents such as aliphatic, cycloaliphatic and aromatic hydrocarbon solvents, or halogenated versions of such solvents. The preferred solvents are C12 or lower, straight chain or branched chain, saturated hydrocarbons, C5 to C9 saturated alicyclic or aromatic hydrocarbons or C2 to C6 halogenated hydrocarbons. Most preferred are C12 or lower, straight chain or branched chain hydrocarbons, particularly hexane. Nonlimiting illustrative examples of solvents are butane, pentane, hexane, heptane, cyclopentane, cyclohexane, cycloheptane, methyl cyclopentane, methyl cyclohexane, isooctane, benzene, toluene, xylene, chloroform, chlorobenzenes, tetrachloroethylene, dichloroethane and trichloroethane.

These processes are carried out in a mix-free reactor system, which is one in which substantially no mixing occurs between portions of the reaction mixture that contain polymer chains initiated at different times. Suitable reactors are a continuous flow tubular or a stirred batch reactor. A tubular reactor is well known and is designed to minimize mixing of the reactants in the direction of flow. As a result, reactant concentration will vary along the reactor length. In contrast, the reaction mixture in a continuous flow stirred tank reactor (CFSTR) is blended with the incoming feed to produce a solution of essentially uniform composition everywhere in the reactor. Consequently, the growing chains in a portion of the reaction mixture will have a variety of ages and thus a single CFSTR is not suitable for the process of this invention. However, it is well known that 3 or more stirred tanks in series with all of the catalyst fed to the first reactor can approximate the performance of a tubular reactor. Accordingly, such tanks in series are considered to be in accordance with the present invention.

A batch reactor is a suitable vessel, preferably equipped with adequate agitation, to which the catalyst, solvent, and monomer are added at the start of the polymerization. The charge of reactants is then left to polymerize for a time long enough to produce the desired product. For economic reasons, a tubular reactor is preferred to a batch reactor for carrying out the processes of this invention.

In addition to the importance of the reactor system to make copolymers in accordance with the present invention, the polymerization should be conducted such that:

a. the catalyst system produces essentially one active catalyst species,

b. the reaction mixture is essentially free of chain transfer agents, and

c. the polymer chains are essentially all initiated simultaneously, which is at the same time for a batch reactor or at the same point along the length of the tube for a tubular reactor.

The desired polymer can be obtained if additional solvent and reactants (e.g., at least one of the ethylene, alpha-olefin and diene) are added either along the length of a tubular reactor or during the course of polymerization in a batch reactor. Operating in this fashion may be desirable in certain circumstances to control the polymerization rate or polymer composition. However, it is necessary to add essentially all of the catalyst at the inlet of the tube or at the onset of batch reactor operation to meet the requirement that essentially all polymer chains are initiated simultaneously.

Accordingly, processes in accordance with the present invention are carried out:

(a) in at least one mix-free reactor,

(b) using a catalyst system that produces essentially one active catalyst species,

(c) using at least one reaction mixture which is essentially transfer agent-free, and

(d) in such a manner and under conditions sufficient to initiate propagation of essentially all polymer chains simultaneously.

Since the tubular reactor is the preferred reactor system for carrying out processes in accordance with the present invention, the following illustrative descriptions and examples are drawn to that system, but will apply to other reactor systems as will readily occur to the artisan having the benefit of the present disclosure.

In practicing processes in accordance with the present invention, use is preferably made of at least one tubular reactor. Thus, in its simplest form, such a process would make use of but a single reactor. However, as would readily occur to the artisan having the benefit of the present disclosure, more than one reactor could be used, either in parallel for economic reasons, or in series with multiple monomer feed to vary intramolecular composition.

For example, various structures can be prepared by adding additional monomer(s) during the course of the polymerization, as shown in FIG. 4, wherein composition is plotted versus position along the contour length of the chain. The Intra-CD of curve 1 is obtained by feeding all of the monomers at the tubular reactor inlet or at the start of a batch reaction. In comparison, the Intra-CD of curve 2 can be made by adding additional ethylene at a point along the tube or, in a batch reactor, where the chains have reached about half their length. The Intra-CD's of Curve 3 requires multiple feed additions. The Intra-CD of curve 4 can be formed if additional comonomer rather than ethylene is added. This structure permits a whole ethylene composition range to be omitted from the chain. In each case, a third or more comonomers may be added.

The composition of the catalyst used to produce alpha-olefin copolymers has a profound effect on copolymer product properties such as compositional dispersity and MWD. The catalyst utilized in practicing processes in accordance with the present invention should be such as to yield essentially one active catalyst species in the reaction mixture. More specifically, it should yield one primary active catalyst species which provides for substantially all of the polymerization reaction. Additional active catalyst species could be present, provided the copolymer product is in accordance with the present invention, e.g., narrow MWD and Inter-CD. It is believed that such additional active catalyst species could provide as much as 35% (weight) of the total copolymer. Preferably, they should account for about 10% or less of the copolymer. Thus, the essentially one active species should provide for at least 65% of the total copolymer produced, preferably for at least 90% thereof. The extent to which a catalyst species contributes to the polymerization can be readily determined using the below-described techniques for characterizing catalyst according to the number of active catalyst species.

Techniques for characterizing catalyst according to the number of active catalyst species are within the skill of the art, as evidenced by an article entitled "Ethylene-Propylene Copolymers. Reactivity Ratios, Evaluation and Significance", C. Cozewith and G. Ver Strate, Macromolecules, 4, 482 (1971), which is incorporated herein by reference.

It is disclosed by the authors that copolymers made in a continuous flow stirred reactor should have an MWD characterized by Mw /Mn =2 and a narrow Inter-CD when one active catalyst species is present. By a combination of fractionation and gel permeation chromatography (GPC) it is shown that for single active species catalysts the compositions of the fractions vary no more than ±3% about the average and the MWD (weight to number average ratio) for these samples approaches two (2). It is this latter characteristic (Mw /Mn of about 2) that is deemed the more important in identifying a single active catalyst species. On the other hand, other catalysts gave copolymer with an Inter-CD greater than ±10% about the average and multi-modal MWD often with Mw /Mn greater than 10. These other catalysts are deemed to have more than one active species.

Catalyst systems to be used in carrying out processes in accordance with the present invention may be Ziegler catalysts, which may typically include:

(a) a compound of a transition metal, i.e., a metal of Groups I-B, III-B, IVB, VB, VIB, VIIB and VIII of the Periodic Table, and (b) an organometal compound of a metal of Groups I-A, II-A, II-B and III-A of the Periodic Table.

The preferred catalyst system in practicing processes in accordance with the present invention comprises hydrocarbon-soluble vanadium compound in which the vanadium valence is 3 to 5 and organo-aluminum compound, with the proviso that the catalyst system yields essentially one active catalyst species as described above. At least one of the vanadium compound/organo-aluminum pair selected must also contain a valence-bonded halogen.

In terms of formulas, vanadium compounds useful in practicing processes in accordance with the present invention could be: ##STR2## where x=0-3 and R=a hydrocarbon radical;

VCl4 ;

VO(AcAc)2,

where AcAc=acetyl acetonate;

V(AcAc)3 ;

VOClx (AcAc)3-x, (2)

where x=1 or 2; and

VCl3.nB,

where n=2-3 and B=Lewis base capable of making hydrocarbon-soluble complexes with VCl3, such as tetrahydrofuran, 2-methyl-tetrahydrofuran and dimethyl pyridine.

In formula 1 above, R preferably represents a C1 to C10 aliphatic, alicyclic or aromatic hydrocarbon radical such as ethyl (Et), phenyl, isopropyl, butyl, propyl, n-butyl, i-butyl, t-butyl, hexyl, cyclohexyl, octyl, naphthyl, etc. Non-limiting, illustrative examples of formula (1) and (2) compounds are vanadyl trihalides, alkoxy halides and alkoxides such as VOCl3, VOCl2 (OBu) where Bu=butyl, and VO(OC2 H5)3. The most preferred vanadium compounds are VCl4, VOCl3, and VOCl2 (OR).

As already noted, the co-catalyst is preferably organo-aluminum compound. In terms of chemical formulas, these compounds could be as follows:

______________________________________AlR.sub.3,         Al(OR')R.sub.2AlR.sub. 2 Cl,     R.sub.2 Al--O--AlR.sub.2AlR'RCl            AlR.sub.2 IAl.sub.2 R.sub.3 Cl.sub.3,              andAlRCl.sub.2,______________________________________

where R and R' represent hydrocarbon radicals, the same or different, as described above with respect to the vanadium compound formula. The most preferred organo-aluminum compound is an aluminum alkyl sesquichloride such as Al2 Et3 Cl3 or Al2 (iBu)3 Cl3.

In terms of performance, a catalyst system comprised of VCl4 and Al2 R3 Cl3, preferably where R is ethyl, has been shown to be particularly effective. For best catalyst performance, the molar amounts of catalyst components added to the reaction mixture should provide a molar ratio of aluminum/vanadium (Al/V) of at least about 2. The preferred minimum Al/V is about 4. The maximum Al/V is based primarily on the considerations of catalyst expense and the desire to minimize the amount of chain transfer that may be caused by the organo-aluminum compound (as explained in detail below). Since, as is known certain organo-aluminum compounds act as chain transfer agents, if too much is present in the reaction mixture the Mw /Mn of the copolymer may rise above 2. Based on these considerations, the maximum Al/V could be about 25, however, a maximum of about 17 is more preferred. The most preferred maximum is about 15.

Chain transfer agents for the Ziegler-catalyzed polymerization of alpha-olefins are well known and are illustrated, by way of example, by hydrogen or diethyl zinc for the production of EPM and EPDM. Such agents are very commonly used to control the molecular weight of EPM and EPDM produced in continuous flow stirred reactors. For the essentially single active species Ziegler catalyst systems used in accordance with the present invention, addition of chain transfer agents to a CFSTR reduces the polymer molecular weight but does not affect the molecular weight distribution. On the other hand, chain transfer reactions during tubular reactor polymerization in accordance with the present invention broaden polymer molecular weight distribution and Inter-CD. Thus the presence of chain transfer agents in the reaction mixture should be minimized or omitted altogether. Although difficult to generalize for all possible reactions, the amount of chain transfer agent used should be limited to those amounts that provide copolymer product in accordance with the desired limits as regards MWD and compositional dispersity. It is believed that the maximum amount of chain transfer agent present in the reaction mixture could be as high as about 0.2 mol/mol of transition metal, e.g., vanadium, again provided that the resulting copolymer product is in accordance with the desired limits as regards MWD and compositional dispersity. Even in the absence of added chain transfer agent, chain transfer reactions can occur because propylene and the organo-aluminum cocatalyst can also act as chain transfer agents. In general, among the organo-aluminum compounds that in combination with the vanadium compound yield just one active species, the organo-aluminum compound that gives the highest copolymer molecular weight at acceptable catalyst activity should be chosen. Furthermore, if the Al/V ratio has an effect on the molecular weight of copolymer product, that Al/V should be used which gives the highest molecular weight also at acceptable catalyst activity. Chain transfer with propylene can best be limited by avoiding excessive temperature during the polymerization as described below.

Molecular weight distribution and Inter-CD are also broadened by catalyst deactivation during the course of the polymerization which leads to termination of growing chains. It is well known that the vanadium-based Ziegler catalysts used in accordance with the present invention are subject to such deactivation reactions which depend to an extent upon the composition of the catalyst. Although the relationship between active catalyst lifetime and catalyst system composition is not known at present, for any given catalyst, deactivation can be reduced by using the shortest residence time and lowest temperature in the reactor that will produce the desired monomer conversions.

Polymerizations in accordance with the present invention should be conducted in such a manner and under conditions sufficient to initiate propagation of essentially all copolymer chains simultaneously. This can be accomplished by utilizing the process steps and conditions described below.

The catalyst components are preferably premixed, that is, reacted to form active catalyst outside of the reactor, to ensure rapid chain initiation. Aging of the premixed catalyst system, that is, the time spent by the catalyst components (e.g., vanadium compound and organo-aluminum) in each other's presence outside of the reactor, should preferably be kept within limits. If not aged for a sufficient period of time, the components will not have reacted with each other sufficiently to yield an adequate quantity of active catalyst species, with the result of non-simultaneous chain initiation. Also, it is known that the activity of the catalyst species will decrease with time so that the aging must be kept below a maximum limit. It is believed that the minimum aging period, depending on such factors as concentration of catalyst components, temperature and mixing equipment, could be as low as about 0.1 second. The preferred minimum aging period is about 0.5 second, while the most preferred minimum aging period is about 1 second. While the maximum aging period could be higher, for the preferred vanadium/organo-aluminum catalyst system the preferred maximum is about 200 seconds. A more preferred maximum is about 100 seconds. The most preferred maximum aging period is about 50 seconds. The premixing could be performed at low temperature such as 40° C. or below. It is preferred that the premixing be performed at 25° C. or below, with 15° C. or below being most preferred.

The temperature of the reaction mixture should also be kept within certain limits. The temperature at the reactor inlet should be high enough to provide complete, rapid chain initiation at the start of the polymerization reaction. The length of time the reaction mixture spends at high temperature must be short enough to minimize the amount of undesirable chain transfer and catalyst deactivation reactions.

Temperature control of the reaction mixture is complicated somewhat by the fact that the polymerization reaction generates large quantities of heat. This problem is, preferably, taken care of by using prechilled feed to the reactor to absorb the heat of polymerization. With this technique, the reactor is operated adiabatically and the temperature is allowed to increase during the course of polymerization. As an alternative to feed prechill, heat can be removed from the reaction mixture, for example, by a heat exchanger surrounding at least a portion of the reactor or by well-known autorefrigeration techniques in the case of batch reactors or multiple stirred reactors in series.

If adiabatic reactor operation is used, the inlet temperature of the reactor feed could be about from -50° C. to 150° C. It is believed that the outlet temperature of the reaction mixture could be as high as about 200° C. The preferred maximum outlet temperature is about 70° C. The most preferred maximum is about 50° C. In the absence of reactor cooling, such as by a cooling jacket, to remove the heat of polymerization, it has been determined that the temperature of the reaction mixture will increase from reactor inlet to outlet by about 13° C. per weight percent of copolymer in the reaction mixture (weight of copolymer per weight of solvent).

Having the benefit of the above disclosure, it would be well within the skill of the art to determine the operating temperature conditions for making copolymer in accordance with the present invention. For example, assume an adiabatic reactor and an outlet temperature of 35° C. are desired for a reaction mixture containing 5% copolymer. The reaction mixture will increase in temperature by about 13° C. for each weight percent copolymer or 5 weight percent ×13° C./wt.%=65° C. To maintain an outlet temperature of 35° C., it will thus require a feed that has been prechilled to 35° C.-65° C.=-30° C. In this instance that external cooling is used to absorb the heat of polymerization, the feed inlet temperature could be higher with the other temperature constraints described above otherwise being applicable.

Because of heat removal and reactor temperature limitations, the preferred maximum copolymer concentration at the reactor outlet is 25 wt./100 wt. diluent. The most preferred maximum concentration is 15 wt/100 wt. There is no lower limit to concentration due to reactor operability, but for economic reasons it is preferred to have a copolymer concentration of at least 2 wt/100 wt. Most preferred is a concentration of at least 3 wt/100 wt.

The rate of flow of the reaction mixture through the reactor should be high enough to provide good mixing of the reactants in the radial direction and minimize mixing in the axial direction. Good radial mixing is beneficial not only to both the Intra- and Inter-CD of the copolymer chains but also to minimize radial temperature gradients due to the heat generated by the polymerization reaction. Radial temperature gradients will tend to broaden the molecular weight distribution of the copolymer since the polymerization rate is faster in the high temperature regions resulting from poor heat dissipation. The artisan will recognize the achievement of these objectives is difficult in the case of highly viscous solutions. This problem can be overcome to some extent through the use of radial mixing devices such as static mixers (e.g., those produced by the Kenics Corporation).

It is believed that residence time of the reaction mixture in the mix-free reactor can vary over a wide range. It is believed that the minimum could be as low as about 1 second. A preferred minimum is about 10 seconds. The most preferred minimum is about 15 seconds. It is believed that the maximum could be as high as about 3600 seconds. A preferred maximum is about 1800 seconds. The most preferred maximum is about 900 seconds.

With reference to the accompanying drawings, particularly FIG. 1, reference numeral 1 generally refers to a premixing device for premixing the catalyst components. For purposes of illustration, it is assumed that a copolymer of ethylene and propylene (EPM) is to be produced using as catalyst components vanadium tetrachloride and ethyl aluminum sesqui chloride. The polymerization is an adiabatic, solution polymerization process using hexane solvent for both the catalyst system and the reaction mixture.

The premixing device 1 comprises a temperature control bath 2, a fluid flow conduit 3 and mixing device 4 (e.g., a mixing tee). To mixing device 4 are fed hexane solvent, vanadium tetrachloride and ethyl aluminum sesqui chloride through feed conduits 5, 6 and 7, respectively. Upon being mixed in mixing device 4, the resulting catalyst mixture is caused to flow within conduit 3, optionally in the form of a coiled tube, for a time long enough to produce the active catalyst species at the temperature set by the temperature bath. The temperature of the bath is set to give the desired catalyst solution temperature in conduit 3 at the outlet of the bath.

Upon leaving the premixing device, the catalyst solution flows through conduit 8 into mixing zone 9 to provide an intimate mixing with hexane solvent and reactants (ethylene and propylene) which are fed through conduit 10. Any suitable mixing device can be used, such as a mechanical mixer, orifice mixer or mixing tee. For economic reasons, the mixing tee is preferred. The residence time of the reaction mixture in mixing zone 9 is kept short enough to prevent significant polymer formation therein before being fed through conduit 11 to tubular reactor 12. Alternatively, streams 8 and 10 can be fed directly to the inlet of reactor 12 if the flow rates are high enough to accomplish the desired level of intimate mixing. The hexane with dissolved monomers may be cooled upstream of mixing zone 9 to provide the desired feed temperature at the reactor inlet.

Tubular reactor 12 is shown with optional, intermediate feed points 13-15 where additional monomers (e.g., ethylene as shown) and/or hexane can be fed to the reactor. The optional feeds would be used in the instance where it would be desirable to control the Intra-CD. While the reactor can be operated adiabatically, if desired or necessary to maintain reaction mixture temperature within desired limits, external cooling means such as a cooling jacket surrounding at least a portion of the reactor system 12 can be provided.

With reference to FIG. 2 which schematically illustrates a process for mixing copolymer with lube oil, copolymer product from reactor 12 is fed through conduit 16 to deashing section 17 wherein catalyst residues are removed from the reaction mixture in a known manner (known as deashing). The vanadium and aluminum compound residues are removed by reacting them with water to form hydrocarbon-insoluble hydroxides and then extracting the hydroxides into dilute acid.

After separating the aqueous and hydrocarbon phases, for instance in a gravity settler, the polymer solution, which primarily contains solvent, unreacted monomers and copolymer product (EPM) is fed through conduit 18 to lube oil mixing tank 19. Of course, tank 19 could be a staged series of tanks. Hot lube oil is fed through conduit 20 to mixing tank 19, wherein the remaining reaction mixture is heated up such that the remaining hexane and unreacted monomers are vaporized and removed through recycle conduit 21 through which they flow back for reuse in premixing device 1 following suitable purification to remove any catalyst poisons. The copolymer product, being hydrocarbon-soluble, is now present in the lube oil and is removed from tank 19 as a copolymer-on-oil solution.

Alternatively, the copolymer solution from the gravity settler can be steam distilled with subsequent extrusion drying of the polymer and then mixed with a hydrocarbon mineral oil diluent to produce an oil additive concentrate or lube oil additive.

Having thus described the above illustrative reactor system, it will readily occur to the artisan that many variations can be made within the scope of the present invention. For example, the placement and number of multiple feed sites, the choice of temperature profile during polymerization and the concentrations of reactants can be varied to suit the end-use application.

By practicing processes in accordance with the present invention, alpha-olefin copolymers having very narrow MWD can be made by direct polymerization. Although narrow MWD copolymers can be made using other known techniques, such as by fractionation or mechanical degradation, these techniques are considered to be impractical to the extent of being unsuitable for commercial-scale operation. As regards EPDM made in accordance with the present invention, the products have enhanced cure properties at a given Mooney Viscosity. As regards EPM, the products have good shear stability and excellent low temperature properties which make them especially suitable for lube oil applications. For lube oil applications, the narrower the MWD of the polymer, the better the copolymer is considered to be.

A lubricating oil composition in accordance with the present invention comprises a major amount of basestock lubricating oil (lube oil) of lubricating viscosity which contains an effective amount of viscosity index improver being a copolymer of ethylene and at least one other alpha-olefin as described in detail above. More specifically, the copolymer should have a MWD characterized by at least one of a ratio of Mw /Mn of less than 2 and a ratio of Mz /Mw of less than 1.8. The preferred ratio of Mw /Mn is less than about 1.6, with less than about 1.4 being preferred. The preferred Mz /Mw is less than about 1.5, with less than about 1.3 being most preferred.

It is preferred that the Intra-CD of the copolymer is such that at least two portions of an individual intra-molecularly heterogeneous chain, each portion comprising at least 5 weight percent of said chain, differ in composition from one another by at least 5 weight percent ethylene. The Intra-CD can be such that at least two portions of copolymer chain differ by at least 10 weight percent ethylene. Differences of at least 20 weight percent, as well as, 40 weight percent ethylene are also considered to be in accordance with the present invention.

It is also preferred that the Inter-CD of the copolymer is such that 95 wt.% of the copolymer chains have an ethylene composition that differs from the copolymer average weight percent ethylene composition by 15 wt.% or less. The preferred Inter-CD is about 13% or less, with the most preferred being about 10% or less.

In a most preferred embodiment, the copolymer has all of the MWD, Intra-CD and Inter-CD characteristics described above when incorporated in a lubricating oil or oil additive concentrate composition. In current practice, ethylene-propylene copolymer is most preferred. The preferred ethylene content of the copolymer, on a weight basis, for use as a lube oil additive is about from 30% to 75%.

For lube oil additive applications, it is believed that the copolymer could have a weight average molecular weight as low as about 5,000. The preferred minimum is about 15,000, with about 50,000 being the most preferred minimum. It is believed that the maximum weight average molecular weight could be as high as about 500,000. The preferred maximum is about 300,000, with about 250,000 being the most preferred maximum.

Copolymers of this invention may be employed in lubricating oils as viscosity index improvers or viscosity modifiers in amounts varying broadly from about 0.001 to 49 et.%. The proportions giving the best results will vary somewhat according to the nature of the lubricating oil basestock and the specific purpose for which the lubricant is to serve in a given case. When used as lubricating oils for diesel or gasoline engine crankcase lubricants, the polymer concentrations are within the range of about 0.1 to 15.0 wt.% of the total composition which are amounts effective to provide viscosity index improvements. Typically such polymeric additives are sold as oil additive concentrates wherein the additive is present in amounts of about 5 to 50 wt%, preferably 6 to 25 wt% based on the total amount of hydrocarbon mineral oil diluent for the additive. The polymers of this invention are typically used in lubricating oils based on a hydrocarbon mineral oil having a viscosity of about 2-40 centistokes (ASTM D-445) at 99° C., but lubricating oil basestocks comprised of a mixture of a hydrocarbon mineral oil and up to about 25 wt% of a synthetic lubricating oil such as esters of dibasic acids and complex esters derived from monobasic acids, polyglycols, dibasic acids and alcohols are also considered suitable.

Finished lubricating oils containing the ethylene-alpha-olefin polymers of the present invention will typically contain a number of other conventional additives in amounts required to provide their normal attendant functions and these include ashless dispersants, metal or over-based metal detergent additives, zinc dihydrocarbyl dithiophosphate, anti-wear additives, anti-oxidants, pour depressants, rust inhibitors, fuel economy or friction reducing additives and the like.

The ashless dispersants include the polyalkenyl or borated polyalkenyl succinimide where the alkenyl group is derived from a C3 -C4 olefin, especially polyisobutenyl having a number average molecular weight of about 700 to 5,000. Other well known dispersants include the oil soluble polyol esters of hydrocarbon substituted succinic anhydride, e.g., polyisobutenyl succinic anhydride and the oil soluble oxazoline and lactone oxazoline dispersants derived from hydrocarbon substituted succinic anhydride and di-substituted amino alcohols. Lubricating oils typically contain about 0.5 to 5 wt.% of ashless dispersant.

The metal detergent additives suitable in the oil are known in the art and include one or more members selected from the group consisting of overbased oil-soluble calcium, magnesium and barium phenates, sulfurized phenates, and sulfonates especially the sulfonates of C16 -C50 alkyl substituted benzene or toluene sulfonic acids which have a total base number of about 80 to 300. These overbased materials may be used as the sole metal detergent additive or in combination with the same additives in the netural form but the overall metal detergent additive combination should have a basicity as represented by the foregoing total base number. Preferably they are present in amounts of from about 0.5 to 8 wt.% with a mixture of overbased magnesium sulfurized phenate and neutral calcium sulfurized phenate, obtained from C8 to C12 alkyl phenols being especially useful.

The anti-wear additives useful are the oil-soluble zinc dihydrocarbyldithiophosphate having a total of at least 5 carbon atoms, preferably alkyl groups of C4 -C8, typically used in amounts of about 0.5-6% by weight.

Other suitable conventional viscosity index improvers, or viscosity modifiers, are the olefin polymers such as other ethylene-propylene copolymers (e.g., those disclosed in the prior art as discussed above), polybutene, hydrogenated polymers and copolymers and terpolymers of styrene with isoprene and/or butadiene, polymers of alkyl acrylates or alkyl methacrylates, copolymers of alkyl methacrylates with N-vinyl pyrollidone or dimethylaminoalkyl methacrylate, post-grafted polymers of ethylene-propylene with an active monomer such as maleic anhydride which may be further reacted with alcohol or an alkylene polyamine, styrene-maleic anhydride polymers post-reacted with alcohols and amines and the like. These are used as required to provide the viscosity range desired in the finished oil, in accordance with known formulating techniques.

Examples of suitable oxidation inhibitors are hindered phenols, such as 2,6-ditertiary-butyl-paracresol, amines, sulfurized phenols and alkyl phenothiazines; usually lubricating oil will contain about 0.01 to 3 weight percent of oxidation inhibitor depending on its effectiveness.

Rust inhibitors are employed in very small proportions such as about 0.1 to 1 weight percent with suitable rust inhibitors being exemplified by C9 -C30 aliphatic succinic acids or anhydrides such as dodecenyl succinic anhydride.

Antifoam agents are typically the polysiloxane silicone polymers present in amounts of about 0.01 to 1 weight percent.

Pour point depressants are used generally in amounts of from about 0.01 to about 10.0 wt.%, more typically from about 0.01 to about 1 wt.%, for most mineral oil basestocks of lubricating viscosity. Illustrative of pour point depressants which are normally used in lubricating oil compositions are polymers and copolymers of n-alkyl methacrylate and n-alkyl acrylates, copolymers of di-n-alkyl fumarate and vinyl acetate, alpha-olefin copolymers, alkylated naphthalenes, copolymers or terpolymers of alpha-olefins and styrene and/or alkyl styrene, styrene dialkyl maleic copolymers and the like.

As noted above, copolymer products made in accordance with the present invention have excellent low temperature properties which makes them suitable for lube oil applications. Accordingly, lube oil compositions made in accordance with the present invention preferably have a Mini Rotary Viscosity (MRV) measurement in centipoises (cps) at -25° C. according to ASTM-D 3829 of less than 30,000. A more preferred MRV is less than 20,000, with less than 10,000 being most preferred.

With reference again to processes for making copolymer in accordance with the present invention, it is well known that certain combinations of vanadium and aluminum compounds that can comprise the catalyst system can cause branching and gelation during the polymerization for polymers containing high levels of diene. To prevent this from happening Lewis bases such as ammonia, tetrahydrofuran, pyridine, tributylamine, tetrahydrothiophene, etc., can be added to the polymerization system using techniques well known to those skilled in the art.

EXAMPLE 1

In this example, an ethylene-propylene copolymer was prepared in a conventional continuous flow stirred tank reactor. Catalyst, monomers and solvent were fed to a 3 gallon reactor at rates shown in the accompanying Table I. Hexane was purified prior to use by passing over 4A molecular sieves (Union Carbide, Linde Div. 4A 1/16" pellets) and silica gel (W. R. Grace Co., Davison Chemical Div., PA-400 20-40 mesh) to remove polar impurities which act as catalyst poisons. Gaseous ethylene and propylene were passed over hot (270° C.) CuO (Harshaw Chemical Co., CU1900 1/4" spheres) to remove oxygen followed by mol sieve treatment for water removal and then were combined with the hexane upstream of the reactor and passed through a chiller which provided a low enough temperature to completely dissolve the monomers in the hexane. Polymerization temperature was controlled by allowing the cold feed to absorb the heat of reaction generated by the polymerization. The reactor outlet pressure was controlled at 413 kPa to ensure dissolution of the monomers and a liquid filler reactor.

Catalyst solution was prepared by dissolving 37.4 g of VCl4 in 7 l of purified n-hexane. Cocatalyst consisted of 96.0 g Al2 Et3 Cl3 in 7 l of n-hexane. These solutions were fed to the reactor at rates shown in Table I. For the case of catalyst premixing the two solutions were premixed at 0° C. for 10 seconds prior to entry into the reactor.

Copolymer was deashed by contacting with aqueous base and recovered by steam distillation of the diluent with mill drying of the product to remove residual volatiles. The product so prepared was analyzed for composition, compositional distribution and molecular weight distribution using the techniques discussed in the specification. Results were as in Table I.

The copolymers were essentially compositionally homogeneous with heterogeneity ±3% about the average, i.e. within experimental error.

These results indicate that for copolymer made in a continuous flow stirred reactor the Mw/Mn was about 2 and the Intra-CD was less than 5% ethylene. Catalyst premixing had no effect on Mw/Mn or compositional distribution. Experiments over a range of polymerization conditions with the same catalyst system produced polymers of similar structure.

              TABLE 1______________________________________              Example 1A Example 1B______________________________________Reactor Inlet Temperature (°C.)              -40        -35Reactor Temperature (°C.)              38         37.5Reactor Feed RatesHexane (kg/hr)     39.0       23.7Ethylene (g/hr)    1037       775Propylene (g/hr)   1404       1185VCl.sub.4 (g/hr)   5.41       2.56Al.sub.2 Et.sub.3 Cl.sub.3 (g/hr)              17.4       13.2Catalyst Premixing Not premixed                         0Temperature (°C.)Catalyst Premixing Time (sec)              Not premixed                         10Reactor Residence Time (min)              10.5       17.1Rate of Polymerization (g/hr)              2256       1516Catalyst Efficiency              416        591(g polymer/g V)(--Mw).sup.(a)     1.5 × 10.sup.5                         2.1 × 10.sup.5(--Mw/--Mn).sup.(b)              2.1        1.9(--M.sub.z /--M.sub.w).sup.(a)              1.7        1.7Average Composition              43         47(Ethylene wt. %).sup.(c)______________________________________Composi-tional           Frag-     In-.sup.(e)                            Intra-CD.sup.(f)Distri-  Original  mented    ter   High   Lowbution.sup.(d)  max    min    max  min  CD    Ethylene                                       Ethylene______________________________________Example  48     42     48   45   +5     0     01A                             -1Example  48     42     50   46   +1    +2     01B                             -5______________________________________ .sup.(a) Determined by GPC/LALLS using total scattered light intensity in 1,2,4 trichlorobenzene at 135° C., Chromatix KMX6, specific refractive index increment dn/dt × -.104(g/cc.).sup.1 (see specification) .sup.(b) Determined from an elution timemolecular weight relationship as discussed in the specification, data precision ±.15 .sup.(c) Determined by ASTM D3900 Method A. Data good to ±2% ethylene. .sup.(d) Composition determined on fractions which comprise 520% of the original polymer weight, hexaneisopropyl alcohol is solventnon solvent pair. .sup.(e) InterCD is determined as the difference for 95 wt. % of the polymer between the maximum and minimum of the original polymer and the average composition .sup.(f) Chains fragmented to ca. 5% of their original molecular weight. IntraCD is determined as the difference in composition between the highes ethylene fractions of the original and fragmented chains and between the lowest such fractions.
EXAMPLE 2

This example is seen to illustrate the importance of reaction conditions in practicing methods in accordance with the invention such as catalyst premixing for making narrow MWD polymer with the desired Intra-CD. In examples 2(B.) and 2(C.) the catalyst components were premixed in order to obtain rapid chain initiation. In example 2(A.) the polymerization conditions were similar, but the catalyst components were fed separately to the reactor inlet.

The polymerization reactor was a one-inch diameter pipe equipped with Kenics static mixer elements along its length. Monomers, hexane, catalyst, and cocatalyst were continuously fed to the reactor at one end and the copolymer solution and unreacted monomers were withdrawn from the other end. Monomers were purified and reactor temperature and pressure was controlled as in Example 1.

A catalyst solution was prepared by dissolving 18.5 g of vanadium tetrachloride, VCl4, in 5.01 of purified n-hexane. The cocatalyst consisted of 142 g of ethyl aluminum sesqui chloride, Al2 Et3 Cl3, in 5.0 l of purified n-hexane. In the case of catalyst premixing, the two solutions were premixed at a given temperature (as indicated in TABLE II) for 10 seconds prior to entry into the reactor.

Table II lists the feed rates for the monomers, catalyst, and the residence time of examples 2(A.), (B.), and (C.). Polymer was recovered and analyzed as in Example 1.

FIG. 5 illustrates the polymer concentration-residence time relationship, with concentration being presented in terms of polymer concentration at residence time t (CAt residence time t)/polymer concentration at final t (CFinal t) which exists at the end of the reactor. It is evident that in example 2(B.) the maximum polymerization rate occurs at about zero reaction time indicating fast initiation of all the polymer chains. As a result, a very narrow MWD EPM with (Mw /Mn) equal to 1.3 and (Mz /Mw) of 1.2 was produced through a process in accordance with the present invention. On the other hand, example 2(A.) shows that EPM with Mw /Mn greater than 2.0 and Mz /Mw of 2.0 was obtained when the proper conditions were not used. In this example, lack of premixing of the catalyst components led to a reduced rate of chain initiation and broadened MWD.

Samples of product were fractionated according to the procedure of Example 1 and as disclosed in the specification. Data appear in Table II.

Sample A, made without catalyst premixing, had a broad Inter-CD typical of the prior art (e.g., Junghanns). For samples B and C Inter-CD was much reduced as a result of the premixing.

Intra-CD is shown as the difference between the fractionation data on the fragmented and unfragmented samples. For sample B, the chains are shown to contain segments of at least 6% ethylene higher than that isolatable on the unfragmented material. The residual Inter-CD obscures the analysis of Intra-CD. To make the analysis clearer, sample C was first fractionated and then one fraction (the 3rd) was refractionated showing it to be homogeneous with regard to Inter-CD. Upon fragmentation a compositional dispersity as large as the original whole polymer Inter-CD was obtained. Thus, those chains must have had an Intra-CD of greater than 18%. The 2nd and 3rd fractions, which were similar, comprised more than 70% of the original polymer showing that the Inter-CD which obscured the Intra-CD was only due to a minor portion of the whole polymer.

Since the fractionation procedure might depend on the solvent non-solvent pair used, a second combination, carbon tetrachloride-ethyl acetate was used on the sample C whole polymer. This pair was also used in the prior art. It is apparent from the data of Table II that hexane-isopropanol separated the polymer more efficiently than CCl4 -ethyl acetate.

                                  TABLE II__________________________________________________________________________              Example 2A                     Example 2B                            Example 2C__________________________________________________________________________Reactor Inlet Temperature (°C.)              -20    -10    -10Reactor Outlet Temperature (°C.)              -3     0      0Reactor Feed RatesHexane (kg/hr)     60.3   60.3   60.3Ethylene (kg/hr)   0.4    0.22   0.22Propylene (kg/hr)  3.2    2.0    2.0VCl.sub.4 (g/hr)   2.22   2.22   2.22Al.sub.2 Et.sub.3 Cl.sub.3 (g/hr)              20.5   17.0   17.0Catalyst Premixing Temperature (°C.)              --     0      +10Catalyst Premixing Time (set)              0      10     10Reactor Residence Time (set)              52     50     -35Rate of Polymerization (g/hr)              874    503    426Catalyst Efficiency (g polymer/g VCl.sub.4)              394    227    192(--Mw).sup.(a)     2.1 × 10.sup.5                     1.4 × 10.sup.5                            9.5 × 10.sup.4(--M.sub.z /--M.sub.w).sup.(a)              2.0    1.2    1.2(--Mw/--Mn).sup.(b)              2.70   1.3    1.2Composition (ethene wt. %).sup.(c)              42.4   39.1   41.4__________________________________________________________________________         Original                Fragmented   Intra CD.sup.(g)Compositional Distribution.sup.(d)         max            min max min Inter CD.sup.(f)                             max                                min__________________________________________________________________________         55 25  --  --  +13  --.sup.(e)                                --.sup.(e)                        -17         45 32  51  32  +6   +6 0                        -7         49 34  51  (39)                        +8   +2 --.sup.(e)                        -73rd cut refractionated         42 39  48  32       +8 -10CCl.sub.4 --ethyl acetate         45 34  --  --  --   -- --__________________________________________________________________________ .sup.(a) Determined by GPC/LALLS using total scattered light intensity in 1,2,4 trichlorobenzene at 135° C., Chromatix KMX6, specific refractive index increment dn/dt × -.104 (g/cc.).sup.-1 (see specification) .sup.(b) Determined from an elution timemolecular weight relationship as discussed in the specification, data precision ±.15 .sup.(c) Determined by ASTM D3900 Method A. Data good to ±2% ethylene. .sup.(d) Composition determined on fractions which comprise 520% of the original polymer weight, hexane isopropyl alcohol is solventnon solvent pair.  .sup.(e) In these cases inter CD obscured intra CD so no increase in CD was shown on fragmentation. .sup.(f) InterCD is determined as the difference for 95 wt. % of the polymer between the maximum and minimum of the original polymer and the average composition. .sup.(g) Chains fragmented to ca. 5% of their original molecular weight. InterCD is determined as the difference in composition between the highes ethylene fractions of the original and fragmented chains and between the lowest such fractions.
EXAMPLE 3

This example illustrates the use of additional monomer feed downstream of the reactor inlet (multiple feed points) to vary polymer composition and compositional distribution while maintaining a narrow MWD. In example 3(B.), a second hexane stream containing only ethylene was fed into the reactor downstream of the inlet in addition to those feeds used at the inlet. In example 3(A.), the polymerization conditions were the same except there was no second ethylene feed. The polymerization procedures of example 2(B.) were repeated. The process conditions are listed in Table III.

The data listed in Table III show that the sample made with an additional monomer feed downstream of the reactor inlet had the same MWD as the one made with all the monomer feed at the reactor inlet. This combined with the increases in ethylene composition of the "2nd feed point" sample and the molecular weight of the final sample in example 3(B.) indicate that the monomers in the second feed had been added to the growing polymer chains. Therefore, the Intra-CD of the final product must be as shown schematically in FIG. 6.

It is apparent that since the chains continue to grow down the tube that a variety of structures can be produced by using multiple feed points as noted in the specification.

              TABLE III______________________________________            Example 3B                     Example 3A______________________________________Solvent Temperature (°C.)Main Feed          -10        -10Second Feed        0          --Reactor Outlet Temperature (°C.)              +3         0Reactor Feed RatesHexane (kg/hr)Main Feed          60.7       60.7Second Feed        9.9        --Ethylene (kg/hr)Main Feed          0.22       0.22Second Feed        0.10       --Propylene (kg/hr)  2.0        2.0VCl.sub.4 (g/hr)   2.22       2.22Al.sub.2 Et.sub.3 Cl.sub.3 (g/hr)              17.0       17.0Reactor Residence Time (sec)Before the 2nd feed point              4          --Overall            35         40Premixing Temperature (°C.)              0          0Premixing Time (sec)              6          6Rate of Polymerization (g/hr)              487        401Catalyst Efficiency              219        181(g polymer/g VCl.sub.4)(--Mw)             1.3 × 10.sup.5                         1.0 × 10.sup.5(--M.sub.z /--M.sub.w)              1.2        1.3(--Mw/--Mn)        1.25       1.24Composition (ethylene wt. %)Reactor sample taken right after              55.3       47.6the 2nd feed pointFinal sample       45.4       41.0______________________________________
EXAMPLE 4

The comparison in this example illustrates that narrow MWD EPM can also be produced in a tubular reactor using the vanadium oxytrichloride (VOCl3)-ethyl aluminum sesqui chloride (Al2 Et3 Cl3) system when the conditions described earlier are used. In example 4(B.) the catalyst components were premixed in order to obtain rapid chain initiation. In example 4(A.) the polymerization conditions were the same, but the catalyst components were fed separately to the reactor inlet. The polymerization procedures of example 2(A.) and 2(B.) were repeated. Table IV lists the run conditions.

The data in Table IV indicate that premixing of the catalyst components produces narrow MWD polymers (Mw/Mn=1.8 and Mz /Mw =1.5).

              TABLE IV______________________________________            Example 4A                     Example 4B______________________________________Reactor Inlet Temperature (°C.)              0          0Reactor Outlet Temperature (°C.)              7          12Reactor Feed RatesHexane (kg/hr)     60.2       61.1Ethylene (kg/hr)   0.2        0.4Propylene (kg/hr)  3.6        2.6VOCl.sub.3 (g/hr)  1.73       5.07Al.sub.2 Et.sub.3 Cl.sub.3 (g/hr)              7.44       54.2Premixing Temperature (°C.)              --         10Premixing Time (sec)              --         6Reactor Residence Time (sec)              52         37Rate of Polymerization (g/hr)              685        359Catalyst Efficiency              208        135(g polymer/g V OCl.sub.3)(--Mw)             2.8 × 10.sup.5                         3.3 × 10.sup.5(--M.sub.z /--M.sub.w)              2.7        1.5(--Mw/--Mn)        2.7        1.8Composition (ethylene wt. %)              40         49______________________________________
EXAMPLE 5

This example illustrates that narrow MWD ethylene-propylene-diene copolymers (EPDM) can be produced in a tubular reactor with premixing of the catalyst components. The polymerization procedures of example 2(B.) were repeated, except that a third monomer, 5-ethylidene-2-norbornene (ENB) was also used. The feed rates to the reactor, premixing conditions, and the residence time for example 5(A.) and 5(B.) are listed in Table V. Also shown in Table V are the results of a control polymerization (5C) made in a continuous flow stirred tank reactor.

The copolymer produced was recovered and analyzed by the procedures described in Example 1 above. In addition, the ENB content was determined by refractive index measurement (I. J. Gardner and G. Ver Strate, Rubber Chem. Tech. 46, 1019 (1973)). The molecular weight distribution, rate of polymerization and compositions are shown in Table V.

The data listed in Table V clearly demonstrate that processes in accordance with the present invention also result in very narrow MWD for EPDM.

Sample 5(B.) and 5(C.), a polymer made in a continuous flow stirred reactor with similar composition and molecular weight, were compounded in the following formulation:

______________________________________Polymer                  100High Abrasion Furnace    80Black (PHR)Oil (PHR)                50ZnO (PHR)                2Tetramethylthiuram Di-   1sulfide (PHR)2-Mercaptobenzothiazole  0.5(PHR)S (PHR)                  1.5______________________________________

The cured properties of these compounds are shown below:

______________________________________         5B     Control (5C)______________________________________Cure 160° C./10'Tensile         1334     1276Elong.          570      550100% Mod.       244      261200% Mod.       412      435300% Mod.       600      618400% Mod.       840      841500% Mod.       1160     1102Shore A          78       80Monsanto: 160° C./60', 1° arc, 0-50 Range.sup.(a)(in-lb/dNm)ML.sup.(b)      2.8/3.2  4.0/4.5MH.sup.(c)      37.2/42.0                    35.0/39.6ts2.sup.(d)      2.8      3.0t'90.sup.(e)    22.2     18.5Rate            7.9/8.9  5.9/6.7______________________________________ .sup.(a) Monsanto Rheometer, Monsanto Company (Akron, OH) .sup.(b) ML = Cure meter minimum torque; ASTM D208481 .sup.(c) MH = Cure meter maximum torque; ASTM D208481 .sup.(d) ts2 = Time (in minutes) to 2point rise above minimum torque; AST D208481 .sup.(e) t'90 = Time (in minutes) to reach 90% of maximum torque rise above minimum; ASTM D208481.

These data show that the cure rate of the narrow MWD polymer was greater than that for the continuous flow stirred reactor control polymer even though Mooney viscosity and ENB content were lower for the former. Thus, the benefit of narrow MWD on cure rate is shown.

                                  TABLE V__________________________________________________________________________               Example 5A                      Example 5B                             Example 5C__________________________________________________________________________Reactor             Tubular                      Tubular                             Stirred TankReactor Inlet Temperature (°C.)               0      -20Reactor Outlet Temperature (°C.)               20     -10Reactor Feed RatesHexane (kg/hr)      60.9   60.9Ethylene (kg/hr)    0.65   0.20Propylene (kg/hr)   5.5    2.15Diene (kg/hr)       0.036  0.026VCl.sub.4 (g/hr)    5.24   2.22Al.sub.2 Et.sub.3 Cl.sub.3 (g/hr)               40.4   21.4Catalyst Premixing Temperature (°C.)               0      -20Catalyst Premixing Time (sec)               6      10Reactor Residence Time (sec)               30     48Rate of Polymerization (g/hr)               1479   454Catalyst Efficiency (g polymer/g V Cl.sub.4)               282    205(--Mw)              1.3 × 10.sup.5                      1.2 × 10.sup.5                             1.6(--M.sub.z /--M.sub.w)               1.37   1.30   4.(--Mw/--Mn)         1.44   1.61   4.Mooney Viscosity ML (1 + 8) 100° C.               45     51     55CompositionEthylene wt. %      39.3   39.3   49.ENB wt. %           3.5    4.2    4.5Cure Rate (dNm)     --     8.9    6.7__________________________________________________________________________
EXAMPLE 6

This example illustrates that narrow MWD EPM can be produced in a tubular reactor with a different configuration when the critical process conditions in accordance with the present invention are used. The polymerization reactor consisted of 12 meters of a 3/8" tubing. The experimental procedures of example 2(B.) were repeated. The process conditions are listed in Table VI.

Data listed in Table VI show that this tubular reactor produced polymer with an MWD as narrow as that of polymers made in the 1" pipe used in the previous example.

              TABLE VI______________________________________Reactor Inlet Temperature (°C.)                  -1Reactor Outlet Temperature (°C.)                  30Reactor Feed RatesHexane (kg/hr)         31.1Ethylene (kg/hr)       0.7Propylene (kg/hr)      11VCl.sub.4 (g/hr)       8.27Al.sub.2 Et.sub.3 Cl.sub.3 (g/hr)                  58.5Reactor Residence Time (sec)                  45Catalyst Premixing Temperature (°C.)                  10Catalyst Premixing Time (sec)                  6Rate of Polymerization (g/hr)                  1832Catalyst Efficiency (g polymer/g VCl.sub.4)                  222(--Mw)                 1.4 × 10.sup.5(--M.sub.z /--M.sub.w) 1.4(--Mw/--Mn)            1.5Composition (ethylene wt. %)                  38______________________________________
EXAMPLES 7-10

In these examples, polymers made as described in the previous examples were dissolved in lubricating oil basestock and the viscosity effects were evaluated. The narrow MWD and intramolecular compositional distribution of these polymers provide improvements in MRV (Mini Rotary Viscosity) and SSI (Sonic Shear Index).

MRV: This is a viscosity measurement in centipoises (cps) at -25° C. according to ASTM-D 3829 using the Mini-Rotary Viscometer and is an industry accepted evaluation for the low temperature pumpability of a lubricating oil.

T.E.: This represents Thickening Efficiency and is defined as the ratio of the weight percent of a polyisobutylene (sold as an oil solution by Exxon Chemical Company as Paratone N), having a Staudinger molecular weight of 20,000, required to thicken a solvent-extracted neutral mineral lubricating oil, having a viscosity of 150 SUS at 37.8° C., a viscosity index of 105 and an ASTM pour point of 0° F., (Solvent 150 Neutral) to a viscosity of 12.3 centistokes at 98.9° C., to the weight percent of a test copolymer required to thicken the same oil to the same viscosity at the same temperature.

SSI: This value is Shear Stability Index and measures the stability of polymers used as V.I. improvers in motor oils subjected to high shear rates. In this method the sample under test is blended with a typical basestock to a viscosity increase at 210° F. of 7.0±5 centistokes. Two portions of the blend are successively subjected to sonic shearing forces at a specific power input and a constant temperature for 15 minutes. Viscosities are determined on the blends both before and after the treatment; the decrease in viscosity after the treatment is a measure of the molecular breakdown of the polymer under test. A series of standard samples is used as a reference to establish the correct value for the sample under test. The corrected value is reported as the SSI which is the percent sonic breakdown to the nearest 1%.

In these tests, a Raytheon Model DF 101, 200 watt, 10 kilocycle sonic oscillator was used, the temperature was 37±4° C., power input is 0.75 ampere, time of test is 15.0 minutes ±10 seconds.

EXAMPLE 7

In this example, polymers made as described in Example 1 and 2 were dissolved in lubricating oil to provide a kinematic viscosity of 13.5 centistokes at 100° C. (ASTM D445) SSI was measured in Solvent 150 Neutral basestock (31 cS. min at 100° F., pour point of 50° F. and broad wax distribution). MRV was measured in a Mid-Continent basestock being a mixture of Solvent 100 Neutral (20 cS. Min at 100° F.) and Solvent 250 Neutral (55 cS min. at 100° F.) and having a narrow (C24 -C36) wax distribution and containing 0.2 wt% vinyl acetate fumarate pour depressant (Paraflow 449, Exxon Chemical Co.)

Results are tabulated below:

______________________________________Oil Containing Shear Stability                        PumpabilityCopolymer as     Ethylene Thickening                        SSI   MRV @Described In:     wt %     Efficiency                        % Loss                              -25° C. cps______________________________________Example 1 42       2.8       28    32,500Example 2A     42       3.6       44    270,000Example 2B     39       2.7       18    25,000Example 2C     41        2.06      8    20,000______________________________________

These data clearly show the improvements in SSI and MRV possible with the polymers of the present invention. Example 2B outperformed Example 1 in SSI at the same TE. Both Examples 2B and 2C, made with premixed catalyst, outperformed Example 1 (made as in Ex. 1) from the backmixed reactor, and Example 2A, made with no premixing and having the broad inter CD.

EXAMPLE 8

In this example it is shown that the polymer of Example 3, which was made with multiple ethylene feeds and which retained its narrow MWD even with a second ethylene feed, has good shear stability.

______________________________________Sample           TE     SSI % Loss______________________________________Example 2B       2.7    18Example 3B       2.6    14.5______________________________________

The shear stability of 3B was equivalent to the polymer made with the single feed. Thus, it is possible to tailor compositional distribution without significantly affecting MWD and SSI.

EXAMPLE 9

In this example it is shown that the premixing of the VOCl3 catalyst components of Example 4, which effected a narrowing of MWD, permits a much higher TE polymer to be employed with the same SSI, as shown in Table 9.

              TABLE 9______________________________________Sample           TE     SSI % Loss______________________________________Example 4A       3.8    52Example 4B       4.9    53______________________________________

It should be noted, however, that a polymer of the same TE as the polymer of Example 4A, when made with premixing exhibits much better SSI than the Example 4A

EXAMPLE 10

This example demonstrates a terpolymer in accordance with this invention exhibits the same viscosity improvements. A terpolymer sample was prepared as in Example 5(A). This sample was tested for SSI and MRV. Sample analysis and results appear in Table 10.

              TABLE 10______________________________________    Ethylene ENBSample   wt %     wt %    TE    MRV   SSI, % Loss______________________________________Example 10A    39.3     3.5     2.5   33,000                                 29______________________________________
Citas de patentes
Patente citada Fecha de presentación Fecha de publicación Solicitante Título
US3162620 *4 May 196122 Dic 1964Du PontEthylene polymers prepared in the form of a coherent film at a quiescent liquid catalyst surface
US4135044 *11 Oct 197716 Ene 1979Exxon Research & Engineering Co.Process for achieving high conversions in the production of polyethylene
Otras citas
Referencia
11981 MMI International Symposium on "Transition Metal Catalyzed Polymerizations", Unsolved Problems.
2 *1981 MMI International Symposium on Transition Metal Catalyzed Polymerizations , Unsolved Problems.
3 *Makromol. Chem., Rapid Commun. 3,225 229 (1982), Doi, Y., Ueki, S., Block Copolymerization of Propylene and Ethylene with the Living . . . .
4Makromol. Chem., Rapid Commun. 3,225-229 (1982), Doi, Y., Ueki, S., Block Copolymerization of Propylene and Ethylene with the "Living" . . . .
Citada por
Patente citante Fecha de presentación Fecha de publicación Solicitante Título
US4716207 *4 Sep 198629 Dic 1987Exxon Research & Engineering Co.Nodular copolymers comprising narrow MWD alpha-olefin copolymers coupled by non-conjugated dienes
US4804794 *13 Jul 198714 Feb 1989Exxon Chemical Patents Inc.Viscosity modifier polymers
US4843129 *3 Mar 198627 Jun 1989Exxon Research & Engineering CompanyElastomer-plastic blends
US4874820 *27 Dic 198517 Oct 1989Exxon Research And Engineering CompanyCopolymer compositions containing a narrow MWD component and process of making same
US4882406 *5 Mar 198621 Nov 1989Exxon Research & Engineering CompanyNodular copolymers formed of alpha-olefin copolymers coupled by non-conjugated dienes
US4900461 *13 May 198813 Feb 1990Exxon Chemical Patents Inc.Viscosity modifier polymers (E-98)
US4959436 *27 Jun 198825 Sep 1990Exxon Research And Engineering Co.Narrow MWD alpha-olefin copolymers
US4999403 *28 Oct 198812 Mar 1991Exxon Chemical Patents Inc.Graft polymers of functionalized ethylene-alpha-olefin copolymer with polypropylene, methods of preparation, and use in polypropylene compositions
US5011891 *21 Ago 199030 Abr 1991Exxon Research & Engineering CompanyElastomer polymer blends
US5021595 *2 Mar 19904 Jun 1991Exxon Chemical Patents Inc.Transition metal catalyst composition for olefin polymerization
US5030695 *12 Sep 19889 Jul 1991Exxon Research & Engineering CompanyEnd-capped polymer chains, star and graft copolymers, and process of making same
US5151204 *1 Feb 199029 Sep 1992Exxon Chemical Patents Inc.Oleaginous compositions containing novel ethylene alpha-olefin polymer viscosity index improver additive
US5167848 *30 May 19891 Dic 1992Exxon Chemical Patents Inc.Grafted viscosity index improver
US5177147 *21 Ago 19905 Ene 1993Advanced Elastomer Systems, LpElastomer-plastic blends
US5187246 *26 Jun 199016 Feb 1993Union Carbide Chemicals & Plastics Technology CorporationProcess for making epr resins
US5191042 *25 Sep 19912 Mar 1993Exxon Chemical Patents Inc.Process for preparing alpha-olefin copolymers having a narrow MWD and broad compositional distribution
US5225091 *15 Abr 19916 Jul 1993Exxon Chemical Patents Inc.Ethylene alpha-olefin polymer substituted thiocarboxylic acid lubricant dispersant additives
US5229022 *15 May 199220 Jul 1993Exxon Chemical Patents Inc.Ethylene alpha-olefin polymer substituted mono- and dicarboxylic acid dispersant additives (PT-920)
US5262075 *26 Oct 199216 Nov 1993Exxon Chemical Patents Inc.Multifunctional viscosity index improver exhibitng improved low temperature viscometric properties
US5266223 *4 Dic 199230 Nov 1993Exxon Chemical Patents Inc.Ethylene alpha-olefin polymer substituted mono-and dicarboxylic acid dispersant additives
US5275747 *1 Feb 19904 Ene 1994Exxon Chemical Patents Inc.Derivatized ethylene alpha-olefin polymer useful as multifunctional viscosity index improver additive for oleaginous composition
US5277833 *12 Ago 199211 Ene 1994Exxon Chemical Patents Inc.Ethylene alpha-olefin polymer substituted mono-and dicarboxylic acid lubricant dispersant additives
US5350532 *5 Oct 199327 Sep 1994Exxon Chemical Patents Inc.Borated ethylene alpha-olefin polymer substituted mono- and dicarboxylic acid dispersant additives
US5350807 *25 Jun 199327 Sep 1994Phillips Petroleum CompanyEthylene polymers
US5366647 *9 Sep 199322 Nov 1994Exxon Chemical Patents Inc.Derivatized ethylene alpha-olefin polymer useful as multifunctional viscosity index improver additive for oleaginous composition (PT-796)
US5433757 *29 Ago 199418 Jul 1995Exxon Chemical Patents Inc.Ethylene alpha-olefin polymer substituted mono- and dicarboxylic acid dispersant additives
US5435926 *21 Jun 199425 Jul 1995Exxon Chemical Patents Inc.Ethylene alpha-olefin polymer substituted mono- and dicarboxylic acid dispersant additives
US5446221 *20 May 199429 Ago 1995Exxon Chemical Patents Inc.Oleaginous compositions containing novel ethylene alpha-olefin polymer viscosity index improver additive
US5470812 *15 Nov 199328 Nov 1995Mobil Oil CorporationHigh activity polyethylene catalysts prepared with alkoxysilane reagents
US5475067 *16 Sep 199312 Dic 1995Exxon Chemical Patents Inc.Process for polyolefin production using short residence time reactors
US5498809 *22 May 199512 Mar 1996Exxon Chemical Patents Inc.Polymers derived from ethylene and 1-butene for use in the preparation of lubricant dispersant additives
US5554310 *9 Jun 199410 Sep 1996Exxon Chemical Patents Inc.Trisubstituted unsaturated polymers
US5561091 *2 May 19951 Oct 1996Mobil Oil CorporationHigh activity polyethylene catalyst prepared from an alcohol and silicon tetrachloride
US5567344 *9 Dic 199422 Oct 1996Exxon Chemical Patents Inc.Gel-free dispersant additives useful in oleaginous compositions, derived from functionalized and grafted alpha-olefin polymers
US5578237 *10 Nov 199426 Nov 1996Exxon Chemical Patents Inc.Gel-free α-olefin dispersant additives useful in oleaginous compositions
US5604043 *20 Sep 199318 Feb 1997W.R. Grace & Co.-Conn.Heat shrinkable films containing single site catalyzed copolymers having long chain branching
US5663129 *5 Jun 19952 Sep 1997Exxon Chemical Patents Inc.Gel-free ethylene interpolymer dispersant additives useful in oleaginous compositions
US5663130 *11 Mar 19962 Sep 1997Exxon Chemical Patents IncPolymers derived from ethylene and 1-butene for use in the preparation of lubricant dispersant additives
US5681799 *3 May 199528 Oct 1997Exxon Chemical Patents Inc.Ethylene alpha-olefin/diene interpolymer-substituted carboxylic acid dispersant additives
US5733980 *22 Sep 199531 Mar 1998Exxon Chemical Patents Inc.Ethylene α-olefin block copolymers and methods for production thereof
US5747596 *5 Ago 19965 May 1998Exxon Chemical Patents Inc.Gel-free alpha-olefin dispersant additives useful in oleaginous compositions
US5759967 *16 Jun 19972 Jun 1998Exxon Chemical Patents IncEthylene α-olefin/diene interpolymer-substituted carboxylic acid dispersant additives
US5910530 *19 May 19978 Jun 1999Bridgestone CorporationHigh damping gel derived from extending grafted elastomers and polypropylene
US5912296 *19 May 199715 Jun 1999Bridgestone CorporationExtended polymer composition derived from grafted elastomers and polypropylene
US5939348 *12 Dic 199617 Ago 1999Mobil Oil CorporationCatalyst for the manufacture of polythylene with a narrow molecular weight distribution
US5981643 *9 Oct 19979 Nov 1999Exxon Chemical Patents, Inc.Depression of the glass transition temperature of polyolefins containing cyclic monomers
US5994256 *21 Ene 199830 Nov 1999Mobil Oil CorporationProcess for forming a catalyst precursor for copolymerizing ethylene and an alpha-olefin of 3 to 10 carbon atoms
US6030930 *14 May 199729 Feb 2000Exxon Chemical Patents IncPolymers derived from ethylene and 1-butene for use in the preparation of lubricant disperant additives
US6110880 *24 Jun 199729 Ago 2000Exxon Chemical Patents IncPolyolefin block copolymer viscosity modifier
US6133354 *17 Nov 199817 Oct 2000Bridgestone CorporationCopolymers as additives in thermoplastic elastomer gels
US61842925 Oct 19986 Feb 2001Bridgestone CorporationSoft gel polymers for high temperature use
US619121717 Nov 199820 Feb 2001Bridgestone CorporationGels derived from polypropylene grafted alkyl vinylether-maleimide copolymers
US62043546 May 199820 Mar 2001Bridgestone CorporationSoft compounds derived from polypropylene grafted disubstituted ethylene- maleimide copolymers
US620776312 Jun 199827 Mar 2001Bridgestone CorporationApplication of disubstituted ethylene-maleimide copolymers in rubber compounds
US62488256 May 199819 Jun 2001Bridgestone CorporationGels derived from extending grafted centipede polymers and polypropylene
US624882722 Dic 199719 Jun 2001Bridgestone CorporationCentipede polymers and preparation and application in rubber compositions
US628761312 Dic 199411 Sep 2001Cryovac IncPatch bag comprising homogeneous ethylene/alpha-olefin copolymer
US629138428 Jul 199718 Sep 2001Mobil Oil CorporationHigh activity catalyst prepared with alkoxysilanes
US634256512 May 200029 Ene 2002Exxonmobil Chemical Patent Inc.Elastic fibers and articles made therefrom, including crystalline and crystallizable polymers of propylene
US63508005 Jun 200026 Feb 2002Bridgestone CorporationSoft polymer gel
US635305431 Jul 20005 Mar 2002Bridgestone CorporationAlkenyl-co-maleimide/diene rubber copolymers and applications
US63590648 Sep 200019 Mar 2002Bridgestone CorporationCompound of polyester and polyalkylene grafted comb polymer
US636916629 Sep 20009 Abr 2002Bridgestone CorporationApplication of disubstituted ethylene-maleimide copolymers in rubber compounds
US63841345 Jun 20007 May 2002Bridgestone CorporationPoly(alkenyl-co-maleimide) and maleated polyalkylene grafted with grafting agent, and epoxy polymer
US64172595 Jun 20009 Jul 2002Bridgestone CorporationPolyalkylene grafted centipede polymers
US645189413 Ago 199917 Sep 2002Solvay Engineered PolymersTPO blends containing multimodal elastomers
US64556265 Jun 200124 Sep 2002Bridgestone CorporationGels derived from extending grafted centipede polymers and polypropylene
US64761175 Jun 20005 Nov 2002Bridgestone CorporationGrafted near-gelation polymers having high damping properties
US649247518 Jun 199910 Dic 2002Japan Polyolefins Co., Ltd.Ethylene/α-olefin copolymer
US650056311 May 200031 Dic 2002Exxonmobil Chemical Patents Inc.Elastic films including crystalline polymer and crystallizable polymers of propylene
US651458317 Sep 19974 Feb 2003Cryovac, Inc.High impact strength film containing single site catalyzed copolymer
US659998829 Abr 200229 Jul 2003Bridgestone CorporationCentipede polymers and preparation and application in rubber compositions
US663571512 Ago 199721 Oct 2003Sudhin DattaThermoplastic polymer blends of isotactic polypropylene and alpha-olefin/propylene copolymers
US664231629 Jun 19994 Nov 2003Exxonmobil Chemical Patents Inc.Elastic blends comprising crystalline polymer and crystallizable polym
US675028415 May 200015 Jun 2004Exxonmobil Chemical Patents Inc.Thermoplastic filled membranes of propylene copolymers
US686726022 Abr 200415 Mar 2005Exxonmobil Chemical Patents, Inc.Elastic blends comprising crystalline polymer and crystallizable polymers of propylene
US692179423 Ene 200326 Jul 2005Exxonmobil Chemical Patents Inc.Blends made from propylene ethylene polymers
US69272583 Jul 20039 Ago 2005Exxonmobil Chemical Patents Inc.Elastic blends comprising crystalline polymer and crystallizable polymers of propylene
US69823106 May 20053 Ene 2006Exxonmobil Chemical Patents Inc.Alpha-olefin/propylene copolymers and their use
US69921586 May 200531 Ene 2006Exxonmobil Chemical Patents Inc.Alpha-olefin/propylene copolymers and their use
US69921596 May 200531 Ene 2006Exxonmobil Chemical Patents Inc.Alpha-olefin/propylene copolymers and their use
US69921606 May 200531 Ene 2006Exxonmobil Chemical Patents Inc.Polymerization processes for alpha-olefin/propylene copolymers
US70190813 Jul 200328 Mar 2006Exxonmobil Chemical Patents Inc.Thermoplastic polymer blends of isotactic polypropylene and alpha-olefin/propylene copolymers
US70264035 Abr 200411 Abr 2006Exxonmobil Chemical Patents Inc.Thermoplastic filled membranes of propylene copolymers
US702640414 Ene 200511 Abr 2006Exxonmobil Chemical Patents Inc.Articles made from blends made from propylene ethylene polymers
US70264052 Feb 200511 Abr 2006Exxonmobil Chemical Patents Inc.Blends made from propylene ethylene polymers
US70340782 Feb 200525 Abr 2006Exxonmobil Chemical Patents Inc.Blends made from propylene ethylene polymers
US705316426 Ago 200530 May 2006Exxonmobil Chemical Patents Inc.Thermoplastic polymer blends of isotactic polypropropylene and alpha-olefin/propylene copolymers
US705698226 Ago 20056 Jun 2006Exxonmobil Chemical Patents Inc.Thermoplastic polymer blends of isotactic polypropylene and alpha-olefin/propylene copolymers
US70569929 Dic 20056 Jun 2006Exxonmobil Chemical Patents Inc.Propylene alpha-olefin polymers
US70569939 Dic 20056 Jun 2006Exxonmobil Chemical Patents Inc.Process for producing propylene alpha-olefin polymers
US708421826 Ago 20051 Ago 2006Exxonmobil Chemical Patents Inc.Thermoplastic polymer blends of isotactic polypropylene and alpha-olefin/propylene copolymers
US71056099 Feb 200612 Sep 2006Exxonmobil Chemical Patents Inc.Alpha-olefin/propylene copolymers and their use
US71064379 Dic 200312 Sep 2006Exxonmobil Chemical Patents Inc.On-line measurement and control of polymer product properties by Raman spectroscopy
US711641415 Oct 20023 Oct 2006Exxonmobil Chemical Patents Inc.On-line measurement and control of polymer properties by raman spectroscopy
US71226039 Feb 200617 Oct 2006Exxonmobil Chemical Patents Inc.Alpha-Olefin/propylene copolymers and their use
US713552816 Feb 200514 Nov 2006Exxonmobil Chemical Patents Inc.Thermoplastic polymer blends of isotactic polypropylene and alpha-olefin/propylene copolymers
US715357125 Jul 200326 Dic 2006Exxonmobil Chemical Patents Inc.Silane crosslinkable polyethylene
US71575229 Feb 20062 Ene 2007Exxonmobil Chemical Patents Inc.Alpha-olefin/propylene copolymers and their use
US716667413 Feb 200623 Ene 2007Exxonmobil Chemical Patents Inc.Elastic blends comprising crystalline polymer and crystallizable polymers of propylene
US72023059 Dic 200510 Abr 2007Exxonmobil Chemical Patents Inc.Elastic blends comprising crystalline polymer and crystallizable polymers of propylene
US720537120 Ene 200617 Abr 2007Exxonmobil Chemical Patents Inc.Blends made from propylene ethylene polymers
US722080111 Jun 200222 May 2007Exxonmobil Chemical Patents Inc.Metallocene-produced very low density polyethylenes or linear low density polyethylenes as impact modifiers
US72328712 Abr 200219 Jun 2007Exxonmobil Chemical Patents Inc.Propylene ethylene polymers and production process
US723560718 Ago 200326 Jun 2007Exxonmobil Chemical Patents Inc.Shrink film
US731683330 Jul 19998 Ene 2008Penchiney Emballage Flexible EuropeMulti-layer thermoplastic films and packages made therefrom
US740223530 Jul 200122 Jul 2008The Lubrizol CorporationViscosity improver compositions providing improved low temperature characteristics to lubricating oils
US74824189 Dic 200527 Ene 2009Exxonmobil Chemical Patents Inc.Crystalline propylene-hexene and propylene-octene copolymers
US748312922 Jul 200527 Ene 2009Exxonmobil Chemical Patents Inc.On-line properties analysis of a molten polymer by raman spectroscopy for control of a mixing device
US750512722 Jul 200517 Mar 2009Exxonmobil Chemical Patents Inc.On-line raman analysis and control of a high pressure reaction system
US750512923 Jun 200617 Mar 2009Exxonmobil Chemical Patents Inc.On-line analysis of polymer properties for control of a solution phase reaction system
US752150724 Nov 200321 Abr 2009Exxonmobil Chemical Patents Inc.Polypropylene-based adhesive compositions
US758883021 Feb 200315 Sep 2009Cryovac, Inc.Heat shrinkable films containing single site catalyzed copolymers
US760140922 Ago 200313 Oct 2009Exxonmobil Chemical Patents Inc.Stretch film
US77276389 Dic 20051 Jun 2010Exxonmobil Chemical Patents Inc.Films of propylene copolymers
US780387617 Ene 200628 Sep 2010Exxonmobil Chemical Patent Inc.Processes for producing polymer blends and polymer blend pellets
US780759324 Oct 20065 Oct 2010Dow Global Technologies Inc.Multi-layer, pre-stretched elastic articles
US785525813 Feb 200621 Dic 2010Exxonmobil Chemical Patents Inc.Propylene olefin copolymers
US786743330 May 200811 Ene 2011Exxonmobil Chemical Patents Inc.Polyolefin-based crosslinked articles
US79065886 Oct 200815 Mar 2011Exxonmobil Chemical Patents Inc.Soft heterogeneous isotactic polypropylene compositions
US792816512 Nov 200419 Abr 2011Exxonmobil Chemical Patents Inc.Transparent and translucent crosslinked propylene-based elastomers, and their production and use
US795173226 Ene 200731 May 2011Exxonmobil Chemical Patents Inc.Elastomeric laminates for consumer products
US795187110 Nov 200631 May 2011Exxonmobil Chemical Patents Inc.Curing rubber by hydrosilation
US795187318 Abr 200731 May 2011Exxonmobil Chemical Patents Inc.Linear low density polymer blends and articles made therefrom
US795554019 Ene 20077 Jun 2011Exxonmobil Chemical Patents Inc.Extrusion of thermoplastic elastomers
US798580218 Abr 200826 Jul 2011Exxonmobil Chemical Patents Inc.Synthetic fabrics, components thereof, and methods for making the same
US801309312 Nov 20046 Sep 2011Exxonmobil Chemical Patents Inc.Articles comprising propylene-based elastomers
US801723130 May 200013 Sep 2011Cryovac, Inc.Heat shrinkable films containing single site catalyzed copolymers having long chain branching
US802175922 Dic 199720 Sep 2011Cryovac Inc.Heat shrinkable films containing single site catalyzed copolymers
US802632319 Abr 200727 Sep 2011Exxonmobil Chemical Patents Inc.Propylene ethylene polymers and production process
US81780313 Dic 201015 May 2012Exxonmobil Chemical Patents Inc.Polyolefin-based crosslinked articles
US820246724 Jul 200719 Jun 2012Exxonmobil Chemical Patents Inc.Propylene-based polymer article
US820294127 May 200919 Jun 2012Exxonmobil Chemical Patents Inc.High shrinkage propylene-based films
US82417534 Jun 200714 Ago 2012Exxonmobil Chemical Patents Inc.Composite thermoplastic elastomer structures with high adhesion performance and uses for the same
US824219811 Nov 200914 Ago 2012Exxonmobil Chemical Patents Inc.Polyolefin adhesive compositions
US82474948 Nov 201021 Ago 2012Exxonmobil Chemical Patents Inc.Thermoset compositions with dispersed thermoplastic resin therein and process for making them
US82834009 Dic 20099 Oct 2012Exxonmobil Chemical Patents Inc.Polyolefin adhesive compositions
US830950116 Abr 201013 Nov 2012Exxonmobil Chemical Patents Inc.Ethylene-based copolymers, lubricating oil compositions containing the same, and methods for making them
US831899315 Dic 200527 Nov 2012Exxonmobil Research And Engineering CompanyLubricant blend composition
US833854022 Oct 200825 Dic 2012Dow Global Technologies LlcPolymeric compositions and processes for molding articles
US837804229 Sep 200919 Feb 2013Exxonmobil Chemical Patents Inc.Finishing process for amorphous polymers
US838373124 Feb 200926 Feb 2013Exxonmobil Chemical Patents Inc.Polypropylene-based adhesive compositions
US838945216 Abr 20105 Mar 2013Exxonmobil Chemical Patents Inc.Polymeric compositions useful as rheology modifiers and methods for making such compositions
US843106513 Abr 201230 Abr 2013Exxonmobil Chemical Patents Inc.Polyolefin-based crosslinked articles
US843164226 May 200930 Abr 2013Exxonmobil Chemical Patents Inc.Polyolefin adhesive compositions and articles made therefrom
US843164316 Abr 201030 Abr 2013Exxonmobil Chemical Patents Inc.Polyolefin adhesive compositions and method of making thereof
US847635226 Jun 20092 Jul 2013Exxonmobil Chemical Patents Inc.Elastomeric compositions comprising hydrocarbon polymer additives having improved impermeability
US84924471 Abr 200823 Jul 2013Exxonmobil Chemical Patents Inc.Closed cell propylene-ethylene foam
US850189226 Ago 20116 Ago 2013Exxonmobil Chemical Patents Inc.Propylene ethylene polymers and production process
US851336129 Dic 200820 Ago 2013Bridgestone CorporationInterpolymers containing isobutylene and diene mer units
US852464512 Jul 20103 Sep 2013The Lubrizol CorporationViscosity improver compositions providing improved low temperature characteristics to lubricating oil
US855790626 May 201115 Oct 2013Exxonmobil Chemical Patents Inc.Flame resistant polyolefin compositions and methods for making the same
US85925248 Dic 200826 Nov 2013Exxonmobil Chemical Patents Inc.Thermoplastic elastomer compositions
US860977231 Mar 201117 Dic 2013Exxonmobil Chemical Patents Inc.Elastic films having improved mechanical and elastic properties and methods for making the same
US861771726 Oct 200631 Dic 2013Exxonmobil Chemical Patents Inc.Heat sealable films from propylene and α-olefin units
US861803312 Ene 201131 Dic 2013Exxonmobil Chemical Patents Inc.Ethylene copolymers, methods for their production, and use
US866412914 Nov 20084 Mar 2014Exxonmobil Chemical Patents Inc.Extensible nonwoven facing layer for elastic multilayer fabrics
US86689755 Nov 201011 Mar 2014Exxonmobil Chemical Patents Inc.Fabric with discrete elastic and plastic regions and method for making same
US867402814 Sep 201218 Mar 2014Dow Global Technologies LlcPolymeric compositions and processes for molding articles
US874869324 Sep 200910 Jun 2014Exxonmobil Chemical Patents Inc.Multi-layer nonwoven in situ laminates and method of producing the same
US876583214 Oct 20111 Jul 2014Exxonmobil Chemical Patents Inc.Polyolefin-based crosslinked compositions and methods of making them
US886583824 Nov 201021 Oct 2014Exxonmobil Chemical Patents Inc.Process for forming thermoplastic vulcanizates
US887786715 Oct 20094 Nov 2014Exxonmobil Chemical Patents Inc.Process for forming thermoplastic vulcanizates and extruded articles therefrom
US896276214 Abr 200824 Feb 2015Exxonmobil Chemical Patents Inc.Thermoplastic polymer compositions, methods for making the same, and articles made therefrom
US897533425 Jun 201010 Mar 2015Exxonmobil Chemical Patents Inc.Crosslinkable propylene-based copolymers, methods for preparing the same, and articles made therefrom
US89999077 Jul 20117 Abr 2015Exxonmobil Chemical Patents Inc.Ethylene based copolymer compositions as viscosity modifiers and methods for making them
US900573911 Jun 201014 Abr 2015Exxonmobil Chemical Patents Inc.Laminated articles and their production
US900616118 Ene 201314 Abr 2015Exxonmobil Chemical Patents Inc.Polymeric compositions useful as rheology modifiers and methods for making such compositions
US900633222 Ago 201114 Abr 2015Exxonmobil Chemical Patents Inc.Weatherable and flame-resistant thermoplastic vulcanizates and methods for making them
US916871812 Mar 201027 Oct 2015Exxonmobil Chemical Patents Inc.Method for producing temperature resistant nonwovens
US916872024 Sep 200927 Oct 2015Exxonmobil Chemical Patents Inc.Biaxially elastic nonwoven laminates having inelastic zones
US917524012 Oct 20123 Nov 2015Exxonmobil Chemical Patents Inc.Ethylene-based copolymers, lubricating oil compositions containing the same, and methods for making them
US919406018 May 201224 Nov 2015Exxonmobil Chemical Patents Inc.Polyolefin-based elastic meltblown fabrics
US922788612 Oct 20125 Ene 2016Exxonmobil Chemical Patents Inc.Polymerization process
US923409331 Mar 200812 Ene 2016Exxonmobil Chemical Patents Inc.Thermoplastic vulcanizates
US926055216 Oct 201416 Feb 2016Exxonmobil Chemical Patents Inc.Process to produce polymers from pyridyldiamido transition metal complexes and use thereof
US926063528 Feb 201316 Feb 2016Exxonmobil Chemical Patents Inc.Polyolefin adhesive compositions and methods for preparing the same
US927904710 Mar 20148 Mar 2016Exxonmobil Chemical Patents Inc.Polymer compositions and nonwoven compositions prepared therefrom
US92968378 May 201229 Mar 2016Exxonmobil Chemical Patents Inc.Cooling and pelletizing process for semi-crystalline polymers
US935953528 Feb 20137 Jun 2016Exxonmobil Chemical Patents Inc.Polyolefin adhesive compositions
US941620612 Ene 201116 Ago 2016Exxonmobil Chemical Patents Inc.Lubricating oil compositions and method for making them
US942240822 Sep 201423 Ago 2016Exxonmobil Chemical Patents Inc.Process for forming thermoplastic vulcanizates
US942861919 Ago 201330 Ago 2016Bridgestone CorporationInterpolymers containing isobutylene and diene mer units
US944106022 Nov 201313 Sep 2016Exxonmobil Chemical Patents Inc.Ethylene copolymers, methods for their production, and use
US94876538 Dic 20158 Nov 2016Exxonmobil Chemical Patents Inc.Process of making crosslinked polyolefin polymer blends and compositions prepared thereof
US949893230 Sep 201022 Nov 2016Exxonmobil Chemical Patents Inc.Multi-layered meltblown composite and methods for making same
US95059572 Ago 201329 Nov 2016Exxonmobil Chemical Patents Inc.Polyolefin adhesive compositions comprising nucleating agents for improved set time
US96433882 Dic 20119 May 2017Exxonmobil Chemical Patents Inc.Multilayer films, their methods of production, and articles made therefrom
US97968388 Ene 201624 Oct 2017Exxonmobil Chemical Patents Inc.Polyolefin adhesive compositions and methods of preparing the same
US981592611 Ago 201614 Nov 2017Exxonmobil Chemical Patents Inc.Ethylene copolymers, methods for their production, and use
US20030130430 *23 Ene 200310 Jul 2003Cozewith Charles C.Blends made from propylene ethylene polymers
US20030236177 *14 Feb 200325 Dic 2003Wu Margaret May-SomNovel lubricant blend composition
US20040009314 *21 Feb 200315 Ene 2004Ahlgren Kelly R.Heat shrinkable films containing single site catalyzed copolymers
US20040024138 *25 Jul 20035 Feb 2004Allermann Gerd ArthurSilane crosslinkable polyethylene
US20040038850 *30 Jul 200126 Feb 2004Chor HuangViscosity improver compositions providing improved low temperature characteristics to lubricating oils
US20040048019 *22 Ago 200311 Mar 2004Ohlsson Stefan BertilStretch film
US20040053022 *18 Ago 200318 Mar 2004Ohlsson Stefan BertilShrink film
US20040110886 *24 Nov 200310 Jun 2004Karandinos Anthony G.Polypropylene-based adhesive compositions
US20040116609 *3 Jul 200317 Jun 2004Sudhin DattaElastic blends comprising crystalline polymer and crystallizable polymers of propylene
US20040133364 *9 Dic 20038 Jul 2004Marrow David GeoffreyOn-line measurement and control of polymer product properties by Raman spectroscopy
US20040152842 *11 Jun 20025 Ago 2004Dunaway David B.Metallocene-produced bery low density polyethylenes or linear low density polyethylenes as impact modifiers
US20040198912 *5 Abr 20047 Oct 2004Dharmarajan N. RajaThermoplastic filled membranes of propylene copolymers
US20040233425 *15 Oct 200225 Nov 2004Long Robert L.On-line measurement and control of polymer properties by raman spectroscopy
US20050107529 *12 Nov 200419 May 2005Sudhin DattaArticles comprising propylene-based elastomers
US20050107530 *12 Nov 200419 May 2005Sudhin DattaTransparent and translucent crosslinked propylene-based elastomers, and their production and use
US20050131155 *2 Feb 200516 Jun 2005Cozewith Charles C.Blends made from propylene ethylene polymers
US20050159553 *14 Ene 200521 Jul 2005Charles CozewithArticles made from blends made from propylene ethylene polymers
US20050209109 *10 May 200522 Sep 2005Winemiller Mark DLubricating oil compositions with improved friction properties
US20050250657 *10 Jun 200510 Nov 2005Wu Margaret MNovel lubricant blend composition
US20060062980 *8 Ene 200423 Mar 2006Exxonmobil Chemical Patents Inc.Elastic articles and processes for their manufacture
US20060136149 *8 May 200322 Jun 2006Long Robert LOn-line measurement and control of polymer properties by raman spectroscopy
US20060167184 *30 Dic 200527 Jul 2006Waddell Walter HInnerliners for use in tires
US20060170137 *17 Ene 20063 Ago 2006Yeh Richard CProcesses for producing polymer blends and polymer blend pellets
US20070019190 *22 Jul 200525 Ene 2007Marrow David GOn-line properties analysis of a molten polymer by Raman spectroscopy for control of a mixing device
US20070021586 *22 Jul 200525 Ene 2007Marrow David GOn-line raman analysis and control of a high pressure reaction system
US20070082154 *12 Oct 200512 Abr 2007Benoit AmbroiseMulti-layer films, methods of manufacture and articles made therefrom
US20070254176 *24 Oct 20061 Nov 2007Dow Global Technologies Inc.Multi-Layer, Pre-Stretched Elastic Articles
US20070260016 *18 Abr 20078 Nov 2007Best Steven ALinear low density polymer blends and articles made therefrom
US20070287007 *26 Oct 200613 Dic 2007Michael Glenn WilliamsHeat sealable films
US20080032079 *24 Jul 20077 Feb 2008Abdelhadi SahnounePropylene-based polymer article
US20080114126 *10 Nov 200615 May 2008Blok Edward JCuring rubber by hydrosilation
US20080174042 *19 Ene 200724 Jul 2008Zacarias Felix MExtrusion of thermoplastic elastomers
US20080182116 *26 Ene 200731 Jul 2008Narayanaswami Raja DharmarajanElastomeric laminates for consumer products
US20080299397 *4 Jun 20074 Dic 2008Leander Michiel KenensComposite thermoplastic elastomer structures with high adhesion performance and uses for the same
US20090053959 *15 Ago 200826 Feb 2009Sudhin DattaSoft and Elastic Nonwoven Polypropylene Compositions
US20090105404 *22 Oct 200823 Abr 2009Dow Global Technologies Inc.Polymeric compositions and processes for molding articles
US20090111946 *6 Oct 200830 Abr 2009Sudhin DattaSoft Heterogeneous Isotactic Polypropylene Compositions
US20090153546 *24 Feb 200918 Jun 2009Sharp Kabushiki KaishaDriving circuit for display device, and display device
US20090247656 *1 Abr 20081 Oct 2009Sunny JacobClosed Cell Propylene-Ethylene Foam
US20090280337 *3 Oct 200712 Nov 2009Centre National De La Recherche ScientifiqueMethod for treating surfaces containing si-h groups
US20090298964 *30 May 20083 Dic 2009Sunny JacobPolyolefin-Based Crosslinked Articles
US20090306281 *26 May 200910 Dic 2009Tancrede Jean MPolyolefin Adhesive Compositions and Articles Made Therefrom
US20100036025 *26 Jun 200911 Feb 2010Rodgers Michael BElastomeric Compositions Comprising Hydrocarbon Polymer Additives Having Improved Impermeability
US20100113694 *15 Oct 20096 May 2010Nadella Hari PProcess for Forming Thermoplastic Vulcanizates and Extruded Articles Therefrom
US20100119855 *15 Oct 200913 May 2010Trazollah OuhadiThermoplastic Elastomer with Excellent Adhesion to EPDM Thermoset Rubber and Low Coefficient of Friction
US20100132886 *9 Dic 20093 Jun 2010George RodriguezPolyolefin Adhesive Compositions
US20100137521 *14 Abr 20083 Jun 2010Ravishankar Periagaram SThermoplastic Polymer Compositions, Methods for Making the Same, and Articles Made Therefrom
US20100267914 *12 Mar 201021 Oct 2010Alistair Duncan WestwoodMethod for Producing Temperature Resistant NonWovens
US20100273692 *16 Abr 201028 Oct 2010Rainer KolbEthylene-Based Copolymers, Lubricating Oil Compositions Containing the Same, and Methods for Making Them
US20100273693 *16 Abr 201028 Oct 2010Sudhin DattaPolymeric Compositions Useful as Rheology Modifiers and Methods for Making Such Compositions
US20100273936 *29 Sep 200928 Oct 2010Richard Cheng-Ming YehFinishing Process for Amorphous Polymers
US20100292114 *12 Jul 201018 Nov 2010The Lubrizol CorporationViscosity Improver Compositions Providing Improved LowTemperature Characteristics to Lubricating Oil
US20100305259 *16 Abr 20102 Dic 2010George RodriguezPolyolefin Adhesive Compositions And Method of Making Thereof
US20100316808 *3 May 201016 Dic 2010Gregory Keith HallPolyolefin Compositions for Coating Applications
US20100316820 *12 Mar 201016 Dic 2010Rainer KolbComposite Materials Comprising Propylene-Based Polymer Blend Coatings
US20100331466 *8 Dic 200830 Dic 2010Trazollah OuhadiThermoplastic Elastomer Compositions
US20110020615 *11 Jun 201027 Ene 2011Van Den Bossche Linda MLaminated Articles and Their Production
US20110020619 *11 Jun 201027 Ene 2011Van Den Bossche Linda MPolypropylene-Based Elastomer Coating Compositions
US20110021710 *25 Jun 201027 Ene 2011Sunny JacobCrosslinkable Propylene-Based Copolymers, Methods for Preparing the Same, and Articles Made Therefrom
US20110059277 *26 Ago 201010 Mar 2011Rainer KolbElastomeric Surface Coatings for Plastic Articles
US20110065867 *27 May 200917 Mar 2011Keung Jay KHigh Shrinkage Propylene-Based Films
US20110077317 *3 Dic 201031 Mar 2011Sunny JacobPolyolefin-Based Crosslinked Articles
US20110112238 *31 Mar 200812 May 2011Maria Dolores EllulThermoplastic Vulcanizates
US20110124814 *8 Nov 201026 May 2011Blok Edward JThermoset Compositions with Dispersed Thermoplastic Resin Therein and Process for Making Them
US20110151233 *16 Dic 201023 Jun 2011Invista North America S.A.R.L.Fabric including polyolefin elastic fiber
US20110152462 *16 Dic 201023 Jun 2011Invista North America S.A R.I.Polyolefin elastic fiber
US20110152810 *16 Dic 201023 Jun 2011Invista North America S.A.R.L.Elastic fiber containing an anti-tack additive
US20110160402 *24 Nov 201030 Jun 2011Roche Stephen FProcess for Forming Thermoplastic Vulcanizates
US20110183878 *12 Ene 201128 Jul 2011Rainer KolbEthylene Copolymers, Methods for Their Production, and Use
US20110183879 *12 Ene 201128 Jul 2011Rainer KolbLubricating Oil Compositions and Method for Making Them
US20110184127 *31 Mar 201128 Jul 2011Michael Glenn WilliamsElastic Films Having Improved Mechanical And Elastic Properties And Methods For Making The Same
CN104704012A *1 Oct 201310 Jun 2015埃克森美孚化学专利公司Polymerization process
CN104704012B *1 Oct 201321 Sep 2016埃克森美孚化学专利公司聚合方法
EP1659137A1 *28 Jul 200524 May 2006Kumho Polychem Co., Ltd.Methods of preparing and isolating EP(D)M elastomer at high yields
EP1688459A12 Feb 20069 Ago 2006Advanced Elastomer Systems, L.P.Thermoplastic vulcanizates and their use
EP2045304A221 Dic 20008 Abr 2009ExxonMobil Chemical Patents Inc.Polypropylene-Based Adhesive Compositions
EP2083046A125 Ene 200829 Jul 2009ExxonMobil Chemical Patents Inc.Thermoplastic elastomer compositions
EP2156948A18 Jul 200924 Feb 2010ExxonMobil Chemical Patents Inc.Elastomeric compositions comprising hydrocarbon polymer additives having improved impermeability
EP3214158A18 Ago 20086 Sep 2017ExxonMobil Chemical Patents Inc.Improved olefinic copolymer compositions for viscosity modification of motor oil
WO1986003755A1 *16 Dic 19853 Jul 1986Exxon Research And Engineering CompanyNodular copolymers formed of alpha-olefin copolymers coupled by non-conjugated dienes
WO1987003606A1 *16 Dic 198618 Jun 1987Exxon Research And Engineering CompanyOlefinic chlorosilane and olefinic halide functional group containing polymers and method of forming the same
WO1987003610A1 *16 Dic 198618 Jun 1987Exxon Research And Engineering CompanyCopolymer compositions containing a narrow mwd component and process of making same
WO1987005312A1 *2 Mar 198711 Sep 1987Exxon Research And Engineering CompanyElastomer-plastic blends
WO1991003505A1 *4 Sep 199021 Mar 1991Exxon Chemical Patents Inc.Alpha olefin copolymers having a narrow mwd and broad compositional distribution
WO2005049672A112 Nov 20042 Jun 2005Exxonmobil Chemical Patents Inc.Transparent and translucent crosslinked propylenebased elastomers, and their production and use
WO2007001694A124 May 20064 Ene 2007Exxonmobil Chemical Patents Inc.Functionalized propylene copolymer adheside composition
WO2007002177A121 Jun 20064 Ene 2007Exxonmobil Chemical Patents Inc.Plasticized functionalized propylene copolymer adhesive composition
WO2009026207A118 Ago 200826 Feb 2009Exxonmobil Chemical Patents Inc.Soft and elastic nonwoven polypropylene compositions
WO2009035580A19 Sep 200819 Mar 2009Exxonmobil Research And Engineering CompanyIn-line process for producing plasticized polymers and plasticized polymer blends
WO2009129006A113 Mar 200922 Oct 2009Exxonmobil Chemical Patents Inc.Synthetic fabrics, components thereof, and methods for making the same
WO2009131747A126 Feb 200929 Oct 2009Exxonmobil Chemical Patents Inc.Propylene copolymers in soft thermoplastic blends
WO2010033276A21 Jun 200925 Mar 2010Exxonmobil Oil CorporationMultilayer films having improved sealing properties, their methods of manufacture, and articles made therefrom
WO2011011124A111 Jun 201027 Ene 2011Exxonmobil Chemical Patents Inc.Polypropylene-based elastomer coating compositions
WO2011025587A18 Jul 20103 Mar 2011Exxonmobil Chemical Patents Inc.Polyolefin adhesive compositions and method of making thereof
WO2011041230A124 Sep 20107 Abr 2011Exxonmobil Chemical Patents Inc.Crosslinked polyolefin polymer blends
WO2011053406A113 Sep 20105 May 2011Exxonmobil Chemical Patents Inc.Pressure-sensitive hot melt adhesive compositions
WO2011081746A124 Nov 20107 Jul 2011Exxonmobil Chemical Patents Inc.Process for forming thermoplastic vulcanizates
WO2011087692A215 Dic 201021 Jul 2011Invista Technologies S.A R.L.Stretch articles including polyolefin elastic fiber
WO2011087693A215 Dic 201021 Jul 2011Invista Technologies S.A R.1.Elastic fiber containing an anti-tack additive
WO2011087695A215 Dic 201021 Jul 2011Invista Technologies S.A R.L.Polyolefin elastic fiber
WO2011090861A112 Ene 201128 Jul 2011Exxonmobil Chemical Patents Inc.Lubricating oil compositions and method for making them
WO2011094057A111 Ene 20114 Ago 2011Exxonmobil Chemical Patents Inc.Copolymers, compositions thereof, and methods for making them
WO2011112308A111 Feb 201115 Sep 2011Exxonmobil Chemical Patents Inc.Composite materials comprising propylene-based polymer blend coatings
WO2011129956A122 Mar 201120 Oct 2011Univation Technologies, LlcPolymer blends and films made therefrom
WO2011159400A13 May 201122 Dic 2011Exxonmobil Chemical Patents Inc.Nonwoven fabrics made from polymer blends and methods for making same
WO2012030577A122 Ago 20118 Mar 2012Exxonmobil Chemical Patents Inc.Weatherable and flame-resistant thermoplastic vulcanizates and methods for making them
WO2012050658A117 Ago 201119 Abr 2012Exxonmobil Chemical Patents Inc.Hydrocarbon polymer modifiers
WO2012051239A112 Oct 201119 Abr 2012Exxonmobil Chemical Patents Inc.Polypropylene-based adhesive compositions
WO2012064468A218 Oct 201118 May 2012Exxonmobil Chemical Patents Inc.Meltblown nonwoven compositions and methods for making them
WO2012064469A118 Oct 201118 May 2012Exxonmobil Chemical Patents Inc.Bicomponent fibers and methods for making them
WO2012074599A129 Sep 20117 Jun 2012Exxonmobil Oil CorporationAntistatic films and methods to manufacture the same
WO2012173714A18 May 201220 Dic 2012Exxonmobil Chemical Patents Inc.Cooling and pelletizing process for semi-crystalline polymers
WO2012177376A11 Jun 201227 Dic 2012Exxonmobil Chemical Patents Inc.Elastic nonwoven materials comprising propylene-based and ethylene-based polymers
WO2013055496A114 Sep 201218 Abr 2013Exxonmobil Chemical Patents Inc.Polyolefin-based crosslinked compositions and methods of making them
WO2013081756A130 Oct 20126 Jun 2013Exxonmobil Chemical Patents Inc.Polymer compositions and nonwoven compositions prepared therefrom
WO2013095804A112 Nov 201227 Jun 2013Exxonmobil Chemical Patents Inc.Fibers and nonwoven materials prepared therefrom
WO2013096532A120 Dic 201227 Jun 2013Exxonmobil Research And Engineering CompanyMethod for improving engine fuel efficiency
WO2013133956A218 Feb 201312 Sep 2013Univation Technologies, LlcMethods for making catalyst compositions and polymer products produced therefrom
WO2013134041A228 Feb 201312 Sep 2013Exxonmobil Chemical Patents Inc.Polyolefin adhesive compositions and methods of preparing the same
WO2013158253A112 Mar 201324 Oct 2013Exxonmobil Chemical Patents Inc.Lubricant compositions comprising ethylene propylene copolymers and methods for making them
WO2013158254A112 Mar 201324 Oct 2013Exxonmobil Chemical Patents Inc.Blocky ethylene propylene copolymers and methods for making them
WO2013169485A124 Abr 201314 Nov 2013Exxonmobil Chemical Patents Inc.Compositions and methods for making them
WO2014058663A1 *1 Oct 201317 Abr 2014Exxonmobil Chemical Patents Inc.Polymerization process
WO2014105614A119 Dic 20133 Jul 2014Univation Technologies, LlcMethods of integrating aluminoxane production into catalyst production
WO2016014230A12 Jul 201528 Ene 2016Exxonmobil Chemical Patents Inc.Footwear compositions comprising propylene-based elastomers
WO2016069089A114 Ago 20156 May 2016Exxonmobil Chemical Patents Inc.Polyolefin adhesive compositions for elastic applications
WO2016085457A125 Nov 20142 Jun 2016Exxonmobil Chemical Patents Inc.Method of making thermoplastic vulcanizates and thermoplastic vulcanizates made therefrom
WO2016137556A110 Dic 20151 Sep 2016Exxonmobil Chemical Patents Inc.Process for forming thermoplastic vulcanizates and thermoplastic vulcanizates made therefrom
WO2016195832A119 Abr 20168 Dic 2016Exxonmobil Chemical Patents Inc.Thermoplastic vulcanizates comprising broad molecular weight distribution polypropylene
WO2016204897A113 May 201622 Dic 2016Exxonmobil Chemical Patents Inc.Thermoplastic elastomer compositions comprising ultrahigh molecular weight polyethylene and methods for making the same
WO2017014839A11 Jun 201626 Ene 2017Exxonmobil Chemical Patents Inc.High softening point hydrocarbon resins
WO2017119949A114 Nov 201613 Jul 2017Exxonmobil Chemical Patents Inc.Thermoplastic vulcanizate compositions, articles made therefrom, and methods for making thereof
Eventos legales
FechaCódigoEventoDescripción
19 Jun 1985ASAssignment
Owner name: EXXON RESEARCH AND ENGINEERING COMPANY A DE CORP
Free format text: ASSIGNMENT OF ASSIGNORS INTEREST.;ASSIGNORS:COZEWITH, CHARLES;JU, SHIAW;VERSTRATE, GARY W.;REEL/FRAME:004414/0580;SIGNING DATES FROM 19830614 TO 19830615
3 Ene 1989FPAYFee payment
Year of fee payment: 4
21 Dic 1992FPAYFee payment
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19 Dic 1996FPAYFee payment
Year of fee payment: 12